HisDivineShadow

For some reason my car has gotten an uneven idle, it jumps up and down pretty regularly (between 600-900rpm) when idling, I wonder if it could be related to the other issue which is that the car can stop now and then, but only when standing still. Like if I stop at a red light and sit there, the engine can stop. If I pu it in park I tend to avoid this. Same thing happens sometimes when I start the car and get ready to move, happens maybe 1 in 10 times that it does this.

In 2005-6 the spark plugs, wires, rotor, etc was replaced. Last year I had to replace the rotor again due to corrosion (winter storage + moisture issues), maybe this could also have caused the issues I am having now? Maybe the spark plugs should be replaced again? I've only driven 15,000 miles or so since however.

Rolling Thunder

Ide guess check your EGR system. Its a very typical cause of a surgeing idle. As for if you should do a tune up couldnt hurt dont think it will help in this case but keep in mind alot of maintenece requirements are X miles OR X months whichever comes first.

HisDivineShadow

Hi again, sorry to resurrect this old topic but just what can I do to see if the EGR system is the culprit?

I just replaced all the injectors on this car, this week infact because the old ones (factory) where all failing, got some Bosch III injectors from Fuel Injector Connection and it seemed to help the other issues the car had developed. That is, it would stagger and loose power when driving, now the engine is smoother than it ever has been while driving. But the idling issues are still there. I took a short video to show what it sounds like:
http://www.youtube.com/watch?v=SksKpGOiuQI

So sort of the same issue still, gonna check out the EGR system next time, as soon as I figure out how to diagnose it. I was told it could also be vacuum leaks or the ECM is having issues.

TreeFiddy

Don't forget the IAC valve. Pull EGR and IAC valves, clean out with carb cleaner. You've been putting up with random red light stops for 2 yrs?

HisDivineShadow

Nah the red light stops ceased occurring by themselves way back then, this is only a car that comes out in summer as well so it spends the majority of time in a garage.

This summer though I had issues with the injectors, sadly it didn't cure the uneven idling, I was really sure there that my issues could all be traced to them. Gonna take a multimeter to the IAC and TPS too and see what they say. Not sure which of the three TPS connectors I need to splice into however.

HisDivineShadow

Right, the two upper connections for anyone who might have the same question in the future.

They measured .62-.63v at idle, at WOT they measured 4.39v

Are these figures OK?

Also the car started stopping again, now though it happens when I start it and put in a gear, then it will often stop. I've heard this might be the fuel pump, could that also be responsible for bad idling?

HisDivineShadow

Looks like it's a combo of the ECM chip and the EGR valve that where responsible. After I reburned the chip with factory settings (the chip seemed to have gone a bit off) the engine idled much better, but after a while I noticed it still went up and down in cyclces and sometimes it would even loose power and then surge. After driving a while I would get the SES light because the engine throws a code 32, which is the EGR system.

So I am guessing I should order a new EGR valve and gasket?

I put the logs here:
https://www.thirdgen.org/forums/dfi-...d-memcals.html

falconman

is your a/c working ok? its probabley not it, but the a/c can sometimes cause Idle jumps.

HisDivineShadow

Actually, the AC is not working at all at the moment. Schrader valve got busted and let all the freon leak away so it no longer works.

I've got a new drier/accumulator waiting to be installed, and the schrader valve has been replaced but it's been opened to the atmosphere. Once I find some freon (I might have a lead) I will put in the new drier, vacuum & refill the system. Right now the old drier is there but the A/C Low Pressure Switch was broken and disconnected, I got a new one I haven't bothered putting back.

I'm not sure if such a thing could cause a Code 32? I've just ordered a new EGR valve & gasket though.

falconman

oops, didn't read the code 32. i guess put in the new valve and see where it takes you.

HisDivineShadow

I've been having such a mess of issues with this car this year I can hardly keep up with it myself, injectors, ecm chip, egr valve, radio, wiper functions, it's like the parts got together and went "hey it's been 20 years, lets have a suicide pact!"

And once it's fixed it's up for sale because I can't afford to keep it anymore even if things where not breaking.

WSX123

iTrader: (1)

I was having the same issue, mine turned out to be the EGR Solenoid, its located under the rotor, once i replaced it, it runs nice now

HisDivineShadow

I thought the EGR solenoid was the thing bolted to the side of the plenum.

WSX123

iTrader: (1)

I believe thats the valve, the solenoid should be bolted right under the rotor

HisDivineShadow

Hrm how many valves are there this on this thing anyway? There's the primary EGR valve, the Vapor Canister Purge Valve and now a third valve for the solenoid?

Anyway that there on the side of the TPI with the green connector going into it, thats what I thought was the solenoid.
http://carphotos.cardomain.com/ride_...0005_large.jpg

Stevolwevol

iTrader: (1)

I had this problem and it was my TPS. I'm sure the EGR could also cause the same issues.

HisDivineShadow

I measured my TPS earlier, I was told its within spec.

HisDivineShadow

About the solenoid/thing/whatever on the side of the plenum that I mentioned, I think it might be the MAP sensor, it's got two short vacuum lines in it.

campbellerman

the thin that the two vacuum lines are going to is the EGR solenoid, it is directly under the ignition coil. The MAP sensor is mounted on the upper plenum above the solenoid.

HisDivineShadow

Yeah, got the new EGR valve and installed it last night, took a look at the EGR solenoid at the same time, but I couldn't detect anything wrong with it but then again I got nothing to diagnose it with.

Installed the new valve and the idle is a bit better, still not perfect though, up and down with 50rpms or so, but I took a long drive and it no longer pops a code 32.