Well my car is finally pissing me off now, I have the "surging idle" problem for a while, I replaced the IAC valve, $290 bucks, cleaned the EGR ports and the Fast Idle Thermo valve, even screwed the wax plunger back in, fixed the idle for a while. But now the idle is surging every once in a while again. But now the big problem thats really making me sick is the shudder under acceleration. Its good when the throttle is barely open, like 20% only, but anything over 20% throttle, it shakes really bad until I get over 3000 rpm, then it seems to be fine. 3rd gear sometimes shakes all the way up to 5000, but every other gear seems good after 3000. It really sucks when I get beat off the line by minivans now....Please Help I am driving myself crazy!

 

Is this a 5spd or auto?

 

did you tighten the fitv down? this might be ignition related. Check your entire ignition system.

p.s. vacuum leaks?

 

It is a 5-speed and I had the FITV off last night, everything is tight and I did replace the orings on the valve as well. All the EVAP Hoses are hooked up, just checked them. One thing I havnt done is a full tune-up since I purchased it at 148,000 miles. I am going to do new wires and cap and rotor soon, I will let you know how that turns out.

 

the same thing happens to my friends car please keep us updated!

 

Does the condition exist if the egr valve is disabled?

When was the last time the o2 sensor was replaced?
Has the connections to the TPS (Throttle Position Sensor) been checked?

It sounds like an off-idle lean condition and either could cause it.


P

 

good call on the TPS^

 

Thanks, here's hoping he'll check back and it helps him

P

 

Well sure enough I checked the TP Sensor and it only had .004 volts with the throttle open all the way. Im gonna go with this and then wait for the tune up after I know what a new TP Sensor does. I got one ordered, I will let you all know! Thanks

 

Mine did the same thing when I got it. turned out to be the sparkplug wires jumping through into the head. Pulled them ou and wrapped them with alot of black tape to see if that was it. Sure enough the problem went away. That was 60,000 ago.

Nick

 

I am having the same issue. I have a 1996 LX 5spd with 124k mi on it. I've been looking for a solution. Let us know if the TP Sensor is an issue.

BTW: Any picutres on how to replace the TPS? I dont know where it is.