Engine Stutter below 3k rpm

[maniax]

I have a really rough idle and the car feels sluggish and stutters below 3000rpm. You can really feel the vibration when it's idling or under 3000rpm. There's like no power under 3k.....but after i pass the 3k mark, the car sings like nothing is wrong.

I was wondering if anyone of you had a similar problem. and solution?

My biggest guess right now is that the EGR may be stuck open due to carbon buildup so its letting in exhaust gas in even when it's not needed in the low rpms. But thats just my guess. However, i dont have a check engine light but i never saw the check engine light on ever since i bought the car even when it was running like ****. Is it possible the check engine light bulb is burnt out? or on a 93 the check engine light doesnt come on unless its a real serious issue?


any help is appreciated.
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[v-cam]

get your codes read, clean out your IAC, TB etc..... infact, do your entire intake. You have a block in there somewhere...

There are also a stack of posts on here about rough idle etc. check them out first aswell.

cheers.

[maniax]

ok so i just cleaned the throttle body with some carb cleaner and some of the intake tubing.......the car seems to idle alot better now. not perfect but the vibration is down to a minimal and my idle speed has increased. My idle speed used to always be around 400rpm......now the lowest it goes is about 600rpm so i guess thats a good thing. I will prolly change the pcv valve to see if it will help some more.

I have yet to figure out how to clean the IAC and EGR

[Mike Gerber]

The IAC valve is under the square or diamond shaped port in the base of the throttle body. Just spray throttle body cleaner liberally in to that port. Let it soak for around 10 minutes and then put everything back together and start the car. This usually takes casre of any problems with the valve.

As far as the EGR valve, do a search. It has been brought up several times.

Mike

[v-cam]

You idle should be around 800 rpm. Anything less will cause vibrations and shakes.

[BakaWill]

i had a very similar problem with my gen 2. an ignition tune up did the trick (plugs+wires+cap+rotor+coil). and cleaning the throttle body definately helped.

[ASG14]

Oh damn Kaven, din not see your thread. Like I said, come over and We can do it at my house.

[maniax]

i think i've found the general problem but have not pinpoint it yet.

Today i decided to do a simple pulling the fuel injector connector test on the front bank bcuz the car has been running real bad and i only get 215miles to a tank...which equals 13mpg.

The idea is that if i pull the electric connectors off each cylinder, it would tell me if that cylinder is doing any work.

So I went ahead and pulled the connectors off starting from the left. After i pulled the connector off the first injector, car started stuttering violently. so i knew that cylinder was good. then i did the middle one and got same results. However, when i got to the last one. Nothing happened as i pull the connector off the injector. So i immediately knew that cylinder was not doing any work and is very well the problem i've been having all along. I WAS RUNNING ON JUST 5 CYLINDERS!!!!.

Then i went ahead and checked the spark on that cylinder. Spark plug looked ok. I put a spark tester on the plug wire and saw spark. So i'm guessing spark is ok.

Next I used an universal noid light on the fuel injector connector, and there was light. So that tells me there's signal coming from the PCM to spray fuel. the electrical circuit should be ok.

Now I've narrowed it down to two problems.
It's either the fuel injector itself is clogged/broken or there's a compression problem.

I hope its the fuel injector bcuz a compression problem would be a more serious problem. I cannot do the compression test so i would have to bring it to a mechanic.

So do you guys see any other possibilities that would cause the cylinder to not work? If its the fuel injector, how hard would it be to replace it myself?

Please let me know thanks.