Motor shaking, no power

charlesh · Post by **charlesh** » Sat Sep 10, 2011 7:44 pm

So I was just sitting there minding my own business, when...

I had just driven 70 miles of a 100 mile trip, sitting at a rest area when my neon went crazy. What does this sound like to you?--

I was in idle, and the motor began to stumble a little. I hit the gas to rev it, but then there was no power. It didn't want to rev. I put it in gear, and it REALLY didn't want to rev, in fact it began to die. Over the next 2 minutes, it got worse and worse, until the engine began shaking violently in idle.

I turned it off and let sit for a minute. Now it didn't want to start right away, it took a good 5 seconds of turning over to start it. (Normally, it starts right up.)

That's how things stand right now. When it eventually starts, it runs in idle, the motor shaking, like it wants to jump out of the car.

Any ideas?

Johny · Post by **Johny** » Sat Sep 10, 2011 8:51 pm

Fuel pump is dieing? Do you hear it engaging when you put it into the on position? Is there a constant noise when you're driving it?

That's what I would be checking first..

charlesh · Post by **charlesh** » Sat Sep 10, 2011 9:23 pm

No noise that I remember.

I don't know what it sounds like when the fuel pump engages.

Would a bad fuel pump or clogged fuel filter cause the engine to jump a lot?

Johny · Post by **Johny** » Sat Sep 10, 2011 9:27 pm

It's definitely possible. Did it give you any CEL codes?

charlesh · Post by **charlesh** » Sat Sep 10, 2011 10:17 pm

Yes, now I remember that it did, but I didn't think of it at the time because there are 3 other codes that it gives me normally. I'm used to seeing the cel.

lilschmied · Post by **lilschmied** » Sat Sep 10, 2011 10:37 pm

Sounds like you probably have a cylinder not firing could be a bunch of things I'd start with looking for a bad plug/wire or even the cps. the codes will help though

Leighvi424 · Post by **Leighvi424** » Sat Sep 10, 2011 11:34 pm

it could be a plugged up cat also, would it run normal if you let it sit for a little bit and cool down

WannabeRT · Post by **WannabeRT** » Sun Sep 11, 2011 8:43 pm

My car had the same symptoms awhile back. It was the CPS. Do the key dance and see if it has P0340.

-Mark-

charlesh · Post by **charlesh** » Wed Oct 12, 2011 4:10 am

I got my car back now.

A little more background: a week before it broke down, the battery started dying. A couple days later it was dead. I recharged it overnight the night before I broke down. The battery's 2 years old--cheap Walmart battery.

When I got the car back a couple days ago, the battery was completely dead, so I jumped it. It was idling smooth, and I let it run a while. It was starting a lot better, but still took about a second longer than normal to start.

I did the key dance and got P1684 and P1297--I've had those ever since I bought the car, and they're not in Haynes. The new one was P0171--Fuel injection system too lean.

Today I jumped it again. I had to crank it 4-5 second to start. Once it got going, it idled very rough about 10 seconds then began to idle smooth. It was stumbling a lot. Give it throttle, and it does go up, but then it begins to stumble and almost die. When I disconnected the jumper cables and turned it off, it didn't want to start on its own. Turns over.

I got the codes again, and they were different. No P0171, but there was a new one--P0108--MAP sensor input above acceptable max voltage. wtf, I just changed the MAP sensor 6 months ago, and changed it a year before that.

What can I do to diagnose?

Jenni · Post by **Jenni** » Wed Oct 12, 2011 4:14 am

check the map and tps wiring. they are known for problems

charlesh · Post by **charlesh** » Wed Oct 12, 2011 4:19 am

What should I look for?

Post by **occasional demons** » Wed Oct 12, 2011 7:16 am

Just wiggle them to see if it changes the way it runs, or take the connector apart, and check for breaks. the slides in the connector could also be corroded.

According to my powertrain manuals for the 2.7L, the P1297 code means that there is no significant difference in the voltage from the manifold absolute pressure sensor whether the engine is running or not, where as there should be.
The possible causes are a restricted vacuum connection between the intake manifold and the MAP sensor, the sensor is failed, the connectors are not together, the wires are damaged, or the powertrain control module is faulty. the MAP is mounted on the intake manifold, and you can identify it because its electrical plug has 3 wires: Black/light blue, violet/white, and dark green/red. You can unscrew the bolts that fasten it to the manifold and check that there is nothing restricting the air pathway between the manifold and the sensor and also inspect the gasket that seals the interface. Also look at the plug to the sensor and examine the condition of the three wires for damage to their insulation. If that doesn't solve the problem then if you have a voltmeter I can tell you what it should read on those 3 wires. So re-check the meaning of the P1297 with autozone, but that is what Chrysler classifies that number as being. Have them read it again just to verify. The wires are a ground, a 5 volt supply, and the signal whose voltage should very from 1 to 4 compared to the ground wire as you rev the engine up and down (identified in the order of colors given above). I can give you the pin numbers at the powertrain controlled to verify whether the wires to the sensor are connected.

I would also replace the battery, as it could be causing the system voltage to change enough to mess with the PCM. If it dips too low, the PCM might do some odd things. If you have a meter, check for 5 volts at the TPS and MAP connectors IIRC the center wire is the feed back to the PCM. There should be 5 volts across the two outer pins.

charlesh · Post by **charlesh** » Wed Oct 12, 2011 9:49 pm

To begin with, I'm going to get a new battery tomorrow. Then I'll start by removing the fuel filter/regulator. Is there any way to tell just by looking if the filter is bad? or do you just have to replace it and cross your fingers?

I visually inspected the tps wires and they looked fine. I don't have a volt-meter, but at least tomorrow I'll have a working battery.

Also, if there's a leaky injector, will you be able to see it leaking?

Post by **occasional demons** » Wed Oct 12, 2011 10:41 pm

The filter is usually good for the life of the car/regulator/fuel pump. there is no way to really check it. I doubt the lean code is from that, more likely the bad MAP signal.

You can't see a fuel injector leaking, unless you were to pull all of them with the rail attached.

You could try spraying carb cleaner, or penetrating oil around the IM to check for vacuum leaks.

titansxt · Post by **titansxt** » Wed Oct 12, 2011 10:44 pm

Sounds like a pissed off fuel pump. Just start big and replace that. And hey if it is not that, you have yourself a new fuel pump.

Jenni · Post by **Jenni** » Thu Oct 13, 2011 4:32 am

could also be a stuck catalyst

charlesh · Post by **charlesh** » Thu Oct 13, 2011 4:26 pm

Alright, I got a new battery (free battery--the old one was still under warranty

) and began checking the wires. Wiggling the MAP sensor connector wires, the engine started stumbling pretty bad. Bad connector! Also, the green wire has some kind of a wire connector spliced in it, with bare wire showing. Anyway, I found a connector at the dealership, and I can pick it up tomorrow.

Still, the car starts hard. First try starting, it cranks for 5-10 seconds. After warming up, it starts faster but still a delay. Would the bad connector be enough to do that? or could it be something else, too? When my MAP sensor was bad before, the car always started right up--it just didn't run too well. Fuel pump buzzes loud and clear at key on. I forgot how loud it is. TPS wires seem just fine. You say the fuel filter/regulator should last forever?

But...there's no other codes but the MAP sensor codes. The "fuel too lean" code hasn't come back.

How do I install the MAP sensor connector? Solder the new wires to the old ones?

Post by **occasional demons** » Thu Oct 13, 2011 8:09 pm

The new connector, if it is like the other replacement ones, will be all one color on the wires. Be sure to keep the positions correct.

I would solder and shrink tube for connections.

Generally the only time the filter would clog, is if you get some really bad fuel. I have over 172,000 on mine.

You could check the flow if you want by removing the line from the fuel rail, and having a container, and helper to jumper the fuel pump. I don't believe they give a specific volume tho. If it is flowing pretty well, I would say the filter is fine. (It will flow far more than while running, but this doesn't mean that the pressure is adequate)

If you have a fuel pump failure, then I would consider replacing it, if the new pump module doesn't have one included. Depending on the type of failure, it could put debris into the filter.

charlesh · Post by **charlesh** » Sat Oct 15, 2011 10:26 pm

Here are the positions of the 3 wires on the MAP sensor connector:

1. dark green/red: 1-4v SIGNAL
2. Black/light blue: GROUND
3. violet/white: 5v SUPPLY

My signal wire has a spade connector about 3 inches up from the MAP connector. Is that supposed to be there? or would that just be a fix?

The connector I bought from the dealer is not pre-assembled. Along with the connector and the wires, it comes with several small copper crimps about the thickness of one wire--they're a quarter inch long. I can't figure out what these are for.

It also came with 3 large diameter shrink tubes, larger than the diameter of the 3 wires together. I'm thinking that's to heat shrink the three wires together where they go into the connector--1 to use and the other 2 as extras--but I could be wrong?

charlesh · Post by **charlesh** » Fri Oct 21, 2011 5:45 pm

Fixed the MAP sensor connector. That really helped stabilize the engine. Managed to drive the car 15 miles to the mechanic. Turns out the fuel pressure was only at 18 psi, so I'm having the fuel pump replaced. Like one poster said, now I'll have a brand new fuel pump. I got the OE from the dealer, so it was pricey, over $350 (plus they want the old part back, go figure), but at least I know I'll have reliable equipment on my car. Thanks ya'll for the help.

Post by **occasional demons** » Fri Oct 21, 2011 5:54 pm

Missed your post on the 15th. Glad you got it all figured out. At least the MAP connector did do some good. better than spending all that $$$ at the dealer, and still having a random nagging issue.

That extra connector was not oem.

titansxt · Post by **titansxt** » Fri Oct 21, 2011 9:56 pm

charlesh wrote:Fixed the MAP sensor connector. That really helped stabilize the engine. Managed to drive the car 15 miles to the mechanic. Turns out the fuel pressure was only at 18 psi, so I'm having the fuel pump replaced. Like one poster said, now I'll have a brand new fuel pump. I got the OE from the dealer, so it was pricey, over $350 (plus they want the old part back, go figure), but at least I know I'll have reliable equipment on my car. Thanks ya'll for the help.

charlesh · Post by **charlesh** » Sat Oct 22, 2011 6:11 pm

titansxt wrote:
charlesh wrote:Fixed the MAP sensor connector. That really helped stabilize the engine. Managed to drive the car 15 miles to the mechanic. Turns out the fuel pressure was only at 18 psi, so I'm having the fuel pump replaced. Like one poster said, now I'll have a brand new fuel pump. I got the OE from the dealer, so it was pricey, over $350 (plus they want the old part back, go figure), but at least I know I'll have reliable equipment on my car. Thanks ya'll for the help.

Just to clarify: I got the oe pump from the dealer; I didn't go to the dealer to get it installed.

titansxt · Post by **titansxt** » Sat Oct 22, 2011 11:00 pm

They wanted your old one back? Odd. How did your filter look when you took out the old pump? Mine was a bit gunky.

charlesh · Post by **charlesh** » Sun Oct 23, 2011 4:15 am

yeah, the dealer charges $40 extra if you don't return the old one. Go figure. I don't know why. The guy at the dealer said the manufacturer wants it back for some reason. I have no idea why.

I'm not doing the work myself, I would have no idea how to replace the fuel pump, plus I don't have the time, or probably the tools. I think you have to remove the gas tank to do it. The work will be done Monday, maybe I can get over there to the mechanic and see it before he returns the old part. I'd like to see what makes the pressure go from 58 to 18 psi.

Post by **occasional demons** » Sun Oct 23, 2011 12:36 pm

The tank doesn't need to be dropped. It does help if the tank is not full tho.

If they are charging a core, it is a factory reman part. I don't care what excuse they give. What is the exact PN?

titansxt · Post by **titansxt** » Sun Oct 23, 2011 7:41 pm

occasional demons wrote:The tank doesn't need to be dropped. It does help if the tank is not full tho.

I dropped my tank, with more gas inside than I thought.

charlesh · Post by **charlesh** » Mon Oct 24, 2011 9:11 pm

I don't know the part number. It's the full assembly including the regulator. He did the work today and it's all done. The car runs great. Plus, I fixed the MAP connector before, so no more problems there. I've driven 30 miles now and NO CEL. I've had codes for the last 2 years and it's really strange driving around without that light. I'm still waiting for it to come on.

Lantern04rt · Post by **Lantern04rt** » Mon Oct 24, 2011 11:36 pm

Glad to hear is back to normal , well better then normal