Fuel gauge bottoms out and then rises on take off.

Drawz · Post by **Drawz** » Sat Oct 04, 2014 6:31 pm

I am new to posting on this forum but I have been reading it a lot over the past week since I bought my 04 Neon SXT with a manual transmission. This thing runs and drives but is a beater, I paid next to nothing for it with intent on just slowly fixing it up. The interior is immaculate and the body is in pretty good shape with just a few minor scratches and dings here and there, but the engine has at least 266k on it. I'm assuming the gear in the differential that spins the vehicle speed sensor has popped out of place because I have changed the VSS with no avail and the hole it mounts in seemed empty if you will. So my speedo and odometer do not function. The only code i have is the one for the VSS i forget the number. (I did have 2 evap codes but i replaced a busted air filter box and fixed the issue, and there was a cam shaft position sensor code that was fixed with a new sensor.) The transmission was allegedly replaced with a rebuilt one in the last 18 months. This is the first "stick shift" i've ever owned but i did learn to drive one 12 or so years ago as a teenager. Needless to say I'm not an expert at driving this thing yet. I can drive it all day, in traffic, starting on a hill etc without stalling it out or getting in a wreck, however sometimes taking off can be a little rough/jerky. Still trying to hone in that sweet spot i suppose. The question at hand is that when my take off is a little rough (sometimes the problem happens on a smooth take off) my fuel gauge will drop all the way to E, fuel light will come on and it will ding and then slowly rise back up. And its not that its close to E and its just sloshing below, it will drop from a full tank to E and climb back up. It can take a few minutes for it to raise back up to accurate. My first guess is the fuel pump assembly in the tank, but i can't confirm it and dont want to change it out on a hunch. I've looked around this site and some others and couldn't really find anything on it. On a scarier note, a couple times I've noticed the oil light come on under the same situation. And to add... my motor/tranny mounts are completely shot. I dont think any are actually broke (they could be i just dont know it), they're just ate up and there is a lot of vibration. I have all 4 mounts ready to have them replaced, my mechanic buddy just hasn't had the time to get them swapped yet. That should get taken care of over the next week or so. I'm no mechanic, but I am some what handy and can usually figure things out with the right guidance. Thanks for the help in advance.

Update: When the tank is completely full it doesnt drop to E. It will drop to about an 1/8 below Full. Anything less than 3/4 tank it will drop all the way to E. Im going to go to the junkyard tomorrow and grab a fuel pump assembly, and pressure regulator while im at it, to see if that corrects my issue.

Dranz · Post by **Dranz** » Sun Oct 05, 2014 8:48 pm

I have this issue also. I believe the issue is a blown capacitor that basically tells your fuel gauge the "average" fuel level in your tank. It can be fixed by replacing your fuel level sending unit, or if you wish, the whole fuel pump assembly.

Drawz · Post by **Drawz** » Sun Oct 05, 2014 11:54 pm

That's what I'm hoping for. I don't feel as if im getting enough gas to my engine anyway so I have multiple reasons to swap the whole unit. Dont have a pressure gauge to check if its bad or not and my rail doesnt have the valve to attach it to either so im not 100% its faulty but I'm gonna go for it anyways! The "donor" I'm salvaging from in the JY is in pretty good condition, so I'm hoping i can get away without having to buy a brand new one. Thanks for the input, I'll update when i get it swapped to see if its a fix. I'll have a look at the current fuel pumps board to see if I can pinpoint any bad components.

Post by **occasional demons** » Mon Oct 06, 2014 8:09 am

If the tank is full, and it still does it, it probably isn't a sender float movement issue. Sloshing would be pretty minimal when full.

I would check the wiring at the connector and the cluster connector. it could be the sender wiring inside the tank also. I don't recall seeing any caps on the sender assy, or any mention of them.

I believe the sender smoothing is done in the cluster. When messing with my fuel level signal for other reasons, suddenly breaking/grounding the circuit would not make the gauge change significantly.

I would have to key off and back on to make it correlate with the input signal.

All the vibrations may have damaged the cluster also.

Drawz · Post by **Drawz** » Mon Oct 06, 2014 10:27 pm

So I was able to grab the whole unit at the JY today, and I dont see any caps but the board is backwards to where you cant see any of the components without taking it apart. I may investigate further tomorrow when I get the old assembly out. On a side note I also found a nice shiny chrome fuel rail with a valve on it today! So I'll be able to actually check the fuel pressure on the new/old pump if I can acquire a gauge.

Drawz · Post by **Drawz** » Sat Oct 11, 2014 12:55 am

It's been rainy the past few day's and I haven't had a chance to drop the tank yet, but I will update when I have the chance to get it done.

Dranz · Post by **Dranz** » Wed Oct 15, 2014 10:24 am

The reason I don't think it's a connection issue, is it rises upon braking(on mine). But I personally don't know of anything other than a cap that can give you an average voltage of something without being a computer chip($). So I just assumed chrysler would have used a cap to perform this function at a reduced cost and reduced complexity. I do remember hearing about this prob back in the day on the .org about it being a bad ground somewhere...

Drawz · Post by **Drawz** » Wed Oct 15, 2014 12:05 pm

Mine doesn't rise any faster when I brake, at least not that I've noticed. It just slowly climbs whether braking, accelerating or sitting. But that does make sense except wouldn't it be happening all the time and not just periodically? The cap would hold the average level to prevent the gauge from jumping up and down as the gas in the tank sloshes, so without it I would assume it would constantly be bouncing with every bump or jerk. I've also noticed it doesn't always drop even with a not so smooth take off. So I would put my money on a ground issue as well. Shorting to ground and taking the power from the gauge. (but i would think that would pop a fuse) Or maybe even a hairline cracked cold solder joint that opens occasionally. My 99 caravan had a cracked solder joint and the whole cluster would die periodically. It's still raining and I only have a driveway to work in, no garage, so it'll have to stay a mystery for the time being. My P0440 (i think was the code for evap) has came back on. I thought I fixed it when I replaced my air filter box but it came back. There were two evap codes but this is the only one that came back. Think I'll replace the gas cap and see if that helps any. Will update when I have more insight on the gas gauge issue.[/i]

Post by **occasional demons** » Wed Oct 15, 2014 12:30 pm

If the wire were shorting to ground, it would only read past full, not pop a fuse. The sender is just a variable ground. Have you tried keying off and back on when this happens?

That was the only way I could get my gauge to accurately read sudden changes to resistance. I had a 100 ohm resistor to ground on a switch to simulate a near empty tank. Flipping the switch would not make the gauge drop, unless I keyed off then back on. If there were a cap in the sender side, bypassing it would let the gauge move rapidly.

The gauge movement stability is more than likely all in the cluster circuitry. The fuel gauge also communicates via the PCI bus, the fuel level to the PCM. So it isn't so much an issue of a cheap fix to keep the needle from bouncing.

Drawz · Post by **Drawz** » Thu Oct 30, 2014 5:16 am

So my water pump seized up and broke my timing belt on the highway the other day. (I'm assuming this was the cause. I know my water pump was bad and leaking coolant and it has all the symptoms of a broken belt. I can see the valves not seating all the way through the intake ports, so I'm going forward with the assumption my belt is broken.) Needless to say my fuel gauge is the least of my worries at this point. I've been reading a lot about it online and I think I'm going to attempt to replace the bent valves myself. I definitely can't afford to pay someone to do it and I just bought the car and really don't want to scrap it. I started taking everything apart today but I struggled with the crankshaft pulley bolt. Sprayed some penetrating oil on it and letting it soak over night. I went ahead and removed the top torque mount, throttle body and breather box, intake manifold, batt tray, coil pack and valve cover. I removed the power steering belt but cracked my only 13 MM socket removing the power steering bolts. That's what I get for buying cheap tools I suppose. I'm going to grab a new socket set tomorrow and keep at it. If I run into any issues that I can't figure out by reading I'll start a new thread. If im successful with this job, I'll come back to the fuel gauge later. I was able to get a fuel pressure gauge on the rail before she crapped out on me and the psi was fine. So I think I'll try replacing the cluster before I drop the tank and swap the pump. I was wanting to do a color swap on my cluster "glow" anyhow.

Post by **occasional demons** » Thu Oct 30, 2014 10:12 pm

alpinegreenneon wrote:There is a bolt reinforcement for one of the oil pan bolts cast into the oil pump right behind the crank pulley. I just wedge a large screwdriver against it. I even do this at the junkyard and it works every time. I get underneath with feet toward the back of the car and hold the screwdriver with my left hand and push on the breaker bar with my right.

Or there is my method: a 2 lb sledge, and a 19mm box end wrench. A few good hits on the wrench usually gets the bolt loose. This is mainly for ATX cars.
MTX cars are easier: Put it in 3rd or higher gear, put a screw driver into the brake rotor, and turn the engine so the screwdriver hits the caliper. Then break loose the bolt, or tighten, whichever applies.

Drawz · Post by **Drawz** » Fri Oct 31, 2014 10:50 pm

Thanks. I found that little spot but the cheap screwdriver i used is toast now lol. Good news is I got the crank bolt and pulley off no problem. 1/2 inch breaker bar with a cheater pipe and about 2 foot of extension and it broke her loose. Also got the power steering pump and bracket out of the way. Tomorrow will work and that pain of a bracket in front of the timing belt cover. I have pictures (not that there aren't plenty on the internet) but don't have a place to host them. I will sign up for one and add them when I have the extra time.

Drawz · Post by **Drawz** » Sat Nov 01, 2014 11:19 pm

Got the head broke free and removed today. The pistons are much cleaner than expected. You can still see the honing marks in the cylinders, with just a little carbon build up. I did run Sea Foam through the gas tank and vacuum line at the PCV valve when I first bought it. I dont know what it looked like before, but im surprised with what it is now whether the Sea Foam did it or not. Was able to confirm I do have bent valves. Damn near all of them are bent. I struggled with the exhaust manifold heat shield bolts, they were rusted, rounded and impossible to get a bite on. Ended up bending the shield a little to get to the manifold bolts without removing the shield. Used the rubber coated handle of a bulky channel lock pliers to prevent damaging the valve cover mating side of the head while prying it outward a little. Rented a screw style spring compressor today from the Auto-zone and will continue cleaning the head components and replacing and lapping in new valves. I have Mineral Spirits, Carb cleaner and brake cleaner. Any tips or warnings with any of these while cleaning the lifters/rockers etc? Debating on going to JY and striping one down to get some used valves to clean up and save some money. Need to save every penny I can. I watched a video of a guy cleaning valves with a brass (i think) wire brush wheel on a bench grinder with the valve chucked in a drill knocking off all the carbon build up. Any thoughts on this? 16 new valves isn't exactly something I'm looking forward to buying right now on top of a HG set and timing belt/water pump/tensioner combo plus accessory belts. So any penny saved helps. Probably time to start a separate thread for this since its obviously no longer a fuel gauge discussion.

Drawz · Post by **Drawz** » Sat Nov 01, 2014 11:57 pm

Here are a few pictures, I have more on a friends phone. The close up you can see the valve not seating all the way. My camera is shit so it's not real clear, but they are bent.

Picture of the Neon. 2004 SXT MXT 260k+ on the motor, rebuilt tranny. Go ahead and hate on the fake vents. Can't take them off w/o hurting the paint.

Top of Head

Bottom of Head

Valve Close Up

Drawz · Post by **Drawz** » Sun Nov 02, 2014 4:15 am

After taking the rockers and cam shaft out, I've noticed my journals and bearings are scored pretty bad and all my exhaust lobes are gnarly. Chunks all over them. The rollers on exhaust rockers seem fine, and all of the intake lobes are smooth, its just the larger exhaust lobes that are boogered. So much for only changing valves. On the hunt for a usable JY head.

Post by **occasional demons** » Sun Nov 02, 2014 4:39 am

Yeah, I would just go for using a complete replacement head at this point. Even if you pulled one just to source the valves, you really should have the valves resurfaced, then lap them to the seats.

A decent used head will already have everything mated up.

As far as crosshatch, meh, mine also has 200,000 plus and still has crosshatch. Means nothing since the rings are still beat. The blocks are likely high nickel content, which makes them better for wear.

The VW engines they used in the first couple years in the Omni's were basically the same: Rings wore out before the cylinder walls. At 300,000 plus, I was able to hand push the pistons out the top with no trouble. There was zero ring ridge. Some light honing, and fresh rings, and that engine was back to no oil useage.

It was literally using 2 or more quarts a week.

Oh yeah, hating on the missing vent!

Drawz · Post by **Drawz** » Sun Nov 02, 2014 12:57 pm

Yea, I had planned on cleaning the valves with a fine brass wire brush wheel on a bench grinder with the valves chucked into a drill with tape on end to prevent marking the stem. And lapping them myself. Like the guy in this video here. http://www.youtube.com/watch?v=7GEmuQa3dPY The compound and tool aren't to expensive. I can get a reman head for around $200 shipped, BUT if i can find one that doesn't have a busted up camshaft/journals warped surface at the junk yard, I'd rather spend my time than money at this point. I'm lucky enough to have a few different good you pulls, all with plenty of neons to pick through, within a 30 minute drive from my house. I'll give a update when I've found a good head, reman or not.

Drawz · Post by **Drawz** » Fri Nov 07, 2014 2:57 am

Got a reman head in today. Little disappointed, thought it was going to come with rocker assemblies, but it didn't. I have to send my rockers in with my old head in order to get the warranty so it's only logical that i would get some tested cleaned up rockers with the new head... nope. O'well JY here i come. Any tips on cleaning these rockers/adjusters? I've read a few posts on hydraulic lash adjusters and diesel or kerosene to clean them. But not much on these one piece rockers/adjusters for the SOHC. And the FSM only says to put them in clean oil and pump them up if they have any sponge to them or to replace if damaged, but fails to describe "damage." What if they're all stiff? Any way to tell if they are stuck or working properly? Wouldn't I want to clean the old oil out and pump in fresh oil to avoid tick? Can't seem to find a way to compress the old ones I have and I've been vigilant since I have to send them off any how. There is one exhaust that has sponge to it, but all the others are stiff. Extremely stiff. Any help is appreciated. I am extremely new to engine work, only doing it myself because I have no other options at this time. I'd hate to install a brand new head that has valve train noise from the get go b/c of rockers. I'm still waiting on my head gasket kit and timing component kit to arrive. So I have a little time to get the rockers figured out before I install. Thanks.

Didn't pull it out of box yet. Will grab a combustion shot when I do.

Post by **occasional demons** » Fri Nov 07, 2014 7:24 am

So wait, the place you got the reman head from requires you to send the rocker assy's but gives you none in return?

I would be calling them and asking where the refubished assy's are. You are looking at ~$600 to buy all that stuff new.

Drawz · Post by **Drawz** » Fri Nov 07, 2014 11:29 am

Yea that was my thought. Cam, valves and springs came with the reman but no rocker assemblies. I can grab an assembly from the JY for $10 for the whole assembly but unsure on the best method to clean these guys up and what to look for as far as damage goes. Plenty of info on the hydraulic lash adjusters that are separate from the arms but not much on the one piece combo. I've sent them an email, waiting for response. I got my gasket kit in today. Still waiting on new head bolts and timing components.

EDIT: I just got an email from them and I only have to send them what came with my new head and that the wrong sticker was stuck on my box. Still stuck on best way to go about cleaning/inspecting these rockers/adjuster combo's. Thanks.

Cant read this one very well. Basically says all new seals/gaskets for top end. lol.

Post by **occasional demons** » Fri Nov 07, 2014 12:33 pm

As long as all the plastic retainers/feet are on the rocker lash adjuster tips, they should be good. As far as the squishy ones, those are what I would worry about more than the solid ones.

I would just clean them with brake clean, and re oil everything before assembling.

Edit:
You may find that a lot of the valve train noise was from worn valve guides, and the hydro timing tensioner. After converting to the Litens tensioner, and having new exhaust guides pressed into my head, the engine was very quiet re using the 112,000 rocker assy's.

Drawz · Post by **Drawz** » Fri Nov 07, 2014 2:02 pm

Thanks for the help man. I appreciate it. Will update when I know something new, or dont know something for that matter. Oh while im thinking about it, I know its been talked about but still worried and would like to confirm with you. The FSM calls for a OBD III scanner to do a re-time or whatever. Is that necessary? I dont have nor do I know anyone who has one of these scanners and I dont look forward to buying one. As long as my timing marks line up I'll be good right? If not will I be good enough to drive to a shop for them to do it? Thanks again.

Post by **occasional demons** » Sun Nov 09, 2014 1:01 am

A crank/cam timing re learn is usually not an issue. As long as you get the marks lined up, which is generally simple on an SOHC, it will run just fine.

Drawz · Post by **Drawz** » Sun Nov 16, 2014 7:45 pm

Awesome. That's what I was hoping for. Got my new head on today. Been busy haven't made a lot of progress. Hopefully get her all buttoned up by next weekend depending on the weather. Supposed to be getting some snow tonight. Also went ahead and bought new sensors. Still haven't got my O2 or oil pressure sensors in. Question about the coolant temp sensor. I've read mixed reviews across the org. My coolant sensor doesn't have any sealant on it, do you think I should use some pipe tape or another sealant? Or just leave it. I know if i do use something to make sure I have threads clear at the end to touch the head for a ground, even though chances are the threads will cut through what ever i use making contact anyway. I didnt get my intake manifold bolted up tonight and it is supposed to snow some. She is parked in the driveway, no carport. I did use a towel to cover all exposed intake ports on the head and the hood is latched. Is this sufficient or should I go coat them in some WD-40 to be sure? Probably start snowing any time now lol. I figure it'll be ok, but a second opinion never hurts. Thanks.

Drawz · Post by **Drawz** » Thu Nov 20, 2014 3:40 pm

Made some decent progress yesterday. Took your advice from another thread and picked up some chain vice grips and used a piece of old belt to protect the pulley while torquing the cam bolt down. I turned the engine clockwise multiple times to make sure my marks lined up every time and it was true every time. I have a question though. When I torque down the crank bolt, how do i get the pully to not spin? It is a MTX and i tried what i've read and had a friend put it in high gear and step on the brake but it still spins. I dont know what to do and cant afford another tool. This project has already cost 4x what i had planned on. Thanks.

Post by **occasional demons** » Thu Nov 20, 2014 5:25 pm

As far as the crank bolt: Put it in gear, and put a screwdriver in each brake rotor. then you should be able to hit the 105 ft lb spec.

Hmmm, vise grips on the cam sprocket, what a wonderful idea.

Drawz · Post by **Drawz** » Sun Nov 23, 2014 4:53 am

Mission complete. New head installed. New sensors and all new mounts. Motor and tranny. New fluids, plugs and wires. She drives like a brand new car and I couldn't be happier. Thanks for all the help Demons. On this thread and others. Couldn't have done it without the guidance. First time I've ever cracked open a engine and it was a success. So far anyhow. Time will tell. Fingers crossed.

Post by **occasional demons** » Sun Nov 23, 2014 2:49 pm

You're welcome, that's why the forum is here!

Just did a timing belt yesterday. I position the visegrips so they rest on the water pump sprocket, to guarantee the cam does not move when torquing the bolt. But a cheater bar works too, if you have something handy to use. But if not, the water pump is just the right distance to use as a brace.

Drawz · Post by **Drawz** » Sun Nov 23, 2014 5:10 pm

Good idea. I had a cheater bar laying there and it always helps when in a bind lol. Back to the original thread, I swapped my cluster today to a SRT-4 cluster (mainly for looks, my speedo and odometer dont even work b/c of speedo pinion gear popped out) And the fuel gauge still drops on acceleration. So cluster circuitry is out of the question. I have a JY fuel pump and regulator that are from low mileage neon. Will probably swap that next to see if it fixes the problem. Something else with this new cluster is my ABS light and BRAKE light stays on all the time now. In my old cluster the BRAKE light worked correctly and illuminated when i had my ebrake engaged but my ABS never came on. There is a bulb in my old cluster where the ABS is but it never came on, could be blown I suppose. Do you think this is something with the cluster swap, or is my ABS jacked up? I'm not even certain I have ABS. I would assume i do since its a 04. Thanks again for all the help.

EDIT: I found this on the forum and answered my own question. Or you did rather.

If the brake tubing from the master cylinder goes directly to the firewall, and there is nothing else mounted there/plumbed in, you do not have ABS.

Usually there would not ba a bulb in there, on a base model. If you installed another cluster, from an R/T or an SRT, you would have these lights illuminated. The only reasonable cure is pulling the bulb. Unless you are good at micro soldering...

Just remember there is no parking brake reminder.
_________________
Bill

Just out of curiosity, is there a way to fix it up and make it so the parking brake reminder still works, but not constantly for the abs that it doesnt have? I'm fairly handy with a soldering iron and have a strong industrial electrical background. Just not too familiar with auto wiring. I understand surface mount components are nearly impossible to solder by hand but it might be a task i take on if i ever find another $10 srt cluster.

Post by **occasional demons** » Sun Nov 23, 2014 5:40 pm

For 99% of us, we just pull the bulbs out when installing R/T and SRT clusters.

For the rest, there is this: http://forums.neons.org/viewtopic.php?f ... &p=2021617