Mechanics

PLYMOUTH BREEZE GAS PROBLEM

1996 Plymouth Breeze • 180,000 miles

Had a problem with rough idle at stop for about a month or so now. I have replace the EGR and IAC. Replaced spark plug wires and plugs today (got a multimeter today showed a bad wire on the first cyl.). I am using an Andriod App Torque Pro for my OBD2 readings. RPMs continue to go around 750 and at that point I have a good amount of vibration in the steering wheel. If I get on the gas to about 850 - 900 rps, the vib is gone. I have tried different tricks to raise the rpms by the screw on the throttle body (like disconnecting the tps, pulling 2 pcm fuses disconnecting the battery and even up to unplugging the 4o pin connectors to the pcm.) All to no avail. Initial start will have the rpms where I set them but tap the gas, the rpms come down to my setting for about 2 seconds then slowly drop back down to around 750. And back to steering wheel vibration.

It has a Chrysler 2.0 4-cyl. How can I raise the rpms up? If it is totally controlled by the pcm (which I suspect), what kind of computer / scan tool can give me the extra 100 - 150 rpm's? Any other tips like what sensors I can probe for readings on the multimeter or other things to check?
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Brianposey
November 17, 2012.



No changing the idle speed. It is controlled by the computer.

Check for vacuum leaks. It may be the issue.

Roy

ASEMaster6371
Nov 17, 2012.
Maybe a stupid question but how do I check for the leaks? Spray something on the hoses?

Tiny
Brianposey
Nov 17, 2012.
Look for cracked, broken hoses. If you cannot, get a shop to smoke the intake system for any any leaks

Roy

ASEMaster6371
Nov 17, 2012.
Thanks Roy.

Tiny
Brianposey
Nov 17, 2012.
Looked up smoke testing. So I grabbed some hose and some cheap nasty tasting (and smelling) cigars. I found that my throttle body was not sealed all the way on the underside so I will fix that. While I was in that area, I happened to look at the metal tube that runs from the egr to the throttle body area. Something did not look right. Look closer with a mini mag flashlight and it looked clogged up. Grabbed a small bit of clothes hanger and tried to run it into the tube. No luck. Now I have the tube out and tried to blow through it. No go. I am not a genius but I would have to guess that the tube is not allowing an airflow. Lol. Going to clean it, seal the carb with a new gasket ring and the Wife is out getting me some hose and clamps to replace a couple of small section. Will let you know how things are after I reassemble everything.

Tiny
Brianposey
Nov 21, 2012.
Nope. Did not fix that problem. Me and a friend of mine with over all the seals and sensors and general stuff on the top of the engine. The more we dug, the more stuff we found. Cam Sensor needs a new seal and the wiring to it is shot, so I got a little rewiring to do. Got some silicone work to do too. After all that. We will dig more. Looks like the problem might be a combination of things as far as we can tell. Going to be an adventure.

Tiny
Brianposey
Nov 22, 2012.
Thought I would add some closure to this due to so many on they web leaving you in the air if a car was fixed.

I had 2 problems. 1st up was the ECT (Engine Coolant Temp.) Sensor. The car ran like utter crap the other day so went to checking more sensors. The ECT read something like 6.6 ohms on the check and at minimum should have been 7. Changed that and the engine woke back up. Fixed.

2nd. The was a vacuum leak at the intake manifold. The way that was found was by getting frustrated and bumping the intake manifold with the palm of my hand near the #3 Spark plug. Only then you heard the hiss. Double checked with Mapp Gas. Bumped it and the hiss was gone and Mapp gas did nothing. Bump it until it hissed and the Mapp gas confirmed the leak. Tightened down bolts and boom. Fixed. Will be doing a gasket though soon.
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Tiny
Brianposey
Dec 2, 2012.
Ok, apparently not fixed. I am going to keep adding to this thread even if there are no other replies for other Breeze owners who might run into the same search as I have online.

I did do a new gasket on the intake but a little after that back to a rough idle. I did the smoke and then the Mapp gas trick and found nothing.

Something made me want to check the battery and the Alternator. Voltmeter out and things were off. Reconfirmed at Advance with a full check. Battery way down on CCA and Alternator reading was off. Replaced both and the car smoothed out some. After returning old ones for core charge (car felt better going there). First stoplight back to rough idle and getting a little rougher. Even before the rpms dropped from @850 to @750.

All things I have replaced so far, I found bad with voltage reading or other readings with spec out of a Haynes manual. I did find (the only solution I found with a follow up a month later). A solution someone had by replacing the crankshaft position sensor. I am going to crawl under and backprobe that sensor and see what I get. The book indicates that the check could show if the sensor is bad or if the supply voltage is not there, then the PCM needs to be checked or replaced.

I am frustrated but have not given up yet.

Tiny
Brianposey
Dec 11, 2012.
Was not the Crankshaft sensor. Even though I wish I could post a photo of the hack job of wiring someone did which I fixed.

Of all the things. I never thought about the Evap system. I kept going after Air, Fire and Fuel. I never though of the Evap System until I took off the vacuum hose to the throttle body. The rpms shot up to 1000 and the engine became very smooth. The Canister Purge Valve Solenoid was sticking closed. So after the car got to the specified temp, it was not opening up the flow. The tube from the throttle body would act just like if you had your thumb blocking it.

For those with a Breeze (Mine is a 96 with a 2.0 engine) who may want to test the Purge Valve, it is very simple to do.
Over by the back of the passenger side headlight there is a hose that connects to a plastic tube that runs along the fuel rail. It leads to the Purge Valve. 1. Find where the rubber hose from the evap canister meets the plastic tube.
2. Start the car and get it to running temperature. That could around where the Thermostat opens or your car gets the rough idle.
3. While engine is running, disconnect the hose from the plastic tube.
4. If your engine stays rough and no change at all or very little change, then you probably have a bad Purge valve or maybe a blockage in the line. This test isolates that part of the system.
5. If your engine "wakes up" then the Purge Valve and hoses are probably good and you need to look further back in the Evap system. Like the canister, leak detector and so forth back to the gas tank.

I replace all the rubber hoses then took the compressor and a blower nozzle to make sure the line from the canister and line to the throttle body were clear. New Purge Valve and so far the car has been back to normal. Feels like I even picked up some power when going uphill.

Tiny
Brianposey
Dec 16, 2012.

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