QuestionQUESTION: Ok, Now, I will make sure we don't have 20 Question chains going on this time. I got the car started, it was the distributor that I had to replace. Now the car starts but it idles very rough, once again as a reminder, before I took it apart it ran fine.
Now this is the symptoms and this is what I have tried.
Symptoms, Engine runs rough, Smells abnormal (Like the wrong mixture of Gas/Air). When engine first starts we get whats sorta like a backfire. Very subtle "pop" and if you hand is by the exhaust you feel a larger push of air when it happens. (Sorta like a backfire) And it only seems to happen in idle-2k rpms. The engine sorta feels like a souped up V8. When I rev it to 3k-4k it almost sounds normal. The poping it does seems to have a rhythm, I could be wrong, but it sounds like it could just be 1 cylinder, sometimes it does it, every 1-2 seconds and then you will go 4-5 seconds and not hear it.
I have tried to check for vacuum leeks and could not find any. I took off the EGR pipe and tried to seal the hole in the plenum with my finger and the engine stalls. If I take my finger off of it, it revs up to 3k RPM's.
The car is so close to being in OK condition, dunno what I could have done wrong. I also checked for codes, No codes from the computer or the "On-off-on-off-on" Check. Then again the engine has not been on for more then 1min and I have not tried to drive it yet.
Sebring 2.5L Conv, 2000. Any ideas bud?
ANSWER: Hi Ian,
I think you have put your finger on the part I would encourage you to check: the egr valve. If that valve stem is sticking slightly ajar it will make for a too lean mixture to allow for either starting or if it starts for running smoothly at idle. So notice the stem of the valve has a slot into which you can insert the tip of a screwdriver. Use that to move the stem back and forth and notice that spring-action tries to close it dead stop. If it seems to not close quickly and firmly to a stop then spray some WD-40 on the stem where it enters the valve body and move it some more to loosen it up.
That is the most proximate cause of a poor idle with no codes of which I am aware. Please let me know what you find. The behavior that you got with the pipe removed is as would be expected, but you may not have noticed that the valve itself is ajar.
Roland
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QUESTION: Ok roland, sorry for the long wait to right you back, I wanted to be sure of my tests.
I did what you wanted me to do with the WB-40 and the valve did feel like it was stuck a little but not much. It had decent spring back when I tested it with a flathead. I made sure the screws were tight at the EGR valves (8 pounds) and tried the engine again. Still some poping out the back of the engine (Not much just very little) and I also noticed the Catalytic smelling like old eggs making me think the rich mixture is being burnt in the Catalytic converter. ( and may be also causing it to expload ?, causing the popping sound?)We also have a rouge sensor code being poped it is p0108, We have been playing a round with the map sensor but it is on sometimes when it trows the code.
ANSWER: That code is set if the MAP signal is greater that 4.6V with the rpm from 400-1500 rpm and the tps at 1.0V or less. The manifold vacuum either has to be quite low (perhaps due to a serious leak?) or there is an issue with the wiring or the MAP sensor itself or possibly the pcm. The violet/white wire carries 5V from the pcm pin 61 which is the operating voltage for the baro sensor, the black/light blue is sensor ground to pin 43 and the signal is dark green/red to pin 43. You could watch the voltage on the signal wire which should definitely drop from about 4.7 at rest (depending upon your local barometric pressure) and it should drop quite a bit (to 3V or so) when you start and idle it. If not then see if the signal circuit is open, the sensor is open internally, the sensor ground is faulty, the sensor signal shorted to 5v, and shake the harness when checking these out. Because you had the intake manifold off recently it may be that you have a leak that you haven't found yet.
Roland
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QUESTION: Hey bud, I see a lot of posts on here about EGR valves on engine and I have read though a lot of pages before I decided to ask you this question. The other day we were mentioning of a rough idle off a 2000 Sebring 2.5l engine. The code that was referenced by me was indeed a self inflicted code, it poped cause we were messing with the sensor so much. So this is what I have came down to figure out.
My egr valve was not working, I did take it off, cleaned it, put it back on, and still it was not moving. So I replaced it with a OEM valve (77 Bucks), and that thing is still not moving. Even with the rpms 4-5k that thing does not budge.
And just to confirm the EGR Valve, when my engine is in the rough idle i can move the valve VERY little (.2 inch) and I can get the car to run perfectly with no pinging or backfire.
When I release the screwdriver I instantly start to get pinging and smell my catalytic overheating (and giving off smoke). I check the vacuum hose that goes into the plenum and it did have suction to it, (Felt like a decent amount for idle) so I am not sure what it is to cause that valve not to open.
As we speak I just bought new plenum gaskets and I am making sure all line's for a sealed vacuum are good and there is no massive carbon built up anywhere. Do you have any ideas bud?
PS. There is another vacuum tube on the right back side of the engine (Driver side) By the back plenum bolt hidden in the back, there is that vacuum tube for the EGR Valve, and is that same spot, on the same connection, theres a vacuum hose that goes into a "Bosch" air box thing mounted on the fire wall. Could this be a issue to? Could this be leaking?
Why I ask it could be leaking is when I had my friend help me do the timing belt he was messing around with the car and never told me. And somehow he ended up breaking a rocker arm, Well he never told me he broke anything and I went to start the car first time and the exhaust valve in cylinder #1 rocker was broke so it was coming out of the Intake valve when it opened, causing a ton of exhaust pressure that when into the plenum, so I have a feeling that is why I am having this issue now. Of course I did replace the rocker arm, and the car DID NOT start like that (Thank god) And I changed some lifters there awhile I was at it. Then tightened it to spec.
But I am still not getting and error codes, any ideas?
AnswerHi Ian,
The egr of course is supposed to be closed at idle, so if the rough idle evens out when you open the valve that is an indication that the mixture at idle is too rich. I can't offer any specific as to why that would be, although you might want to verify that the MAP is working properly, due to the 0108 code. What is its signal voltage at idle (smooth idle).
You could check the wiring to the egr solenoid:
pin 1 (gray/yellow) to pin 40 at the pcm, pin 2 (dark green/orange) is the 12V wire from the ASD which in this case comes from pin 6 of the pcm plug. The pcm of course is programmed to operate the egr solenoid by grounding pin 40, but whether it is not activating the solenoid because of the mixture issues is an unknown.
Roland
