Idle Issues I can't seem to fix.....
 

So when I start Lil' Blue (my cars name) it idles funky. Sometimes it will idle at 3k until i drive it for about 5 minutes. Then it will go back to normal. Other times when i start it, it will rev immidiately to 3k and then just die. Other times, It will idle fine. And OTHER times it will idle at like 1.5k and then go to normal .750k. I don't know whats wrong. I am going to try to change the plugs, fuel filter, oil and oil filter, and put some fuel injector cleaner in it. If this doesn't work, anyone have any suggestions? It seems to be a common problem on the 2nd Gens. Thanks a bunch

Seth

On a cold start, the accelerated warmup system (BAC & AWS valves) boost idle speed up to 3k. But this should only be for about 17 seconds.

After that, idle will be at 1.5k and slowly drop to 750k, as the thermowax heats up and moves the primary throttle plate.

Most of what you described is what the engine is supposed to do, but the part about it reving to 3k, then dying isn't. Download a copy of the factory service manual (links at top of page) and adjust the idle, as it describes. The variable resistor, air bypass screw & TPS will all play a role.

Ok. I will do that. I am going out to work on it now so I will update as soon as possbile. Thanks

Ok. Well I replaced the oil and filter. air filter. fuel filter. and spark plugs. runs smoother now. however the rpms now idle at a low 500 and the cars sounds like its about to die. it never does stop running but just chugs when it comes to a stop. the rpms jump between 750 and 500. :dunno: I cant explain it. any ideas???

So you didn't adjust the idle at all yet? Adjust the speed up at least.

In addition to that, check that the intake duct is sealing properly at the AFM and at the intake elbow. If it's loose, it will suck in air that the ECU doesn't know about, and it'll mess up the idle.

Well that helps me out alot, thanks for that post.
That hose actually blew off when my car was idling, I put it back on and tightened it on. and now my car seems almost fine.
/crosses fingers.

Try checking this stuff out.


1)leaking air intake system
2)incorrect idle speed
3)incorrect ignition timing
4)Malfunctioning electronic spark advance system
5)malfunctioning 6-port induction system
6)clogged air fliter
7)bad secondary air injection system water thermo sensor
8)faulty atmospheric pressure sensor
9)faulty throttle sensor
10)primary injector(s) malfunctioning
11)malfunctioning fuel pump control system
12)by-pass air control system/idle speed control system malfunctioning
13)defective secondary air injection system air control valve
14)faulty fast idle operation
15)poor fuel flow at idle
16) faulty air flow meter and/or intake air temperature sensor
17)defective intake air temperature sensor on dynamic chamber(non-t) or air intake pipe(t)
18)defective EGR valve
19)incorrect fuel pressure
20)low compression pressure
21)malfunctioning control unit or control system

Well all, I dont believe it is a vaccuum leak. It idles fine sometimes and then just jumps around sometimes. It sputters at low rpm. Almost like little mini backfires??????????????? Who knows. I am trying to diagnose the problem little by little and day by day. Everything seems to be intact. SO maybe Spark plug wires or clogged fuel injectors???? Could be a coil??? I dont know. Maybe someone will have the same problem.

Like I asked before, have you adjusted the idle at all yet? It doesn't sound like you have.

If not, use the variable resistor to find where the engine idles the smoothest. This is usually in the middle between rich "R" and lean "L". Once that's ok, open the screw on the top of the throttle body (covered w/ rubber cap). This will allow more air into the engine at idle, which will boost the speed. My cars have always run smoother with the idle speed bumped up to 800-900 rpm.

*** Important: jump the initial set coupler before adjusting idle. ****

You also need to consider testing the throttle position sensor (TPS), as it may be out of adjustment or need to be replaced.