i have an 88 crx si and i put on a header and a high flow cat then put a ported throttle body and intake manifold that is for an hf on my car. now it idles up to 4g and back to 800 in a lopeing fashion, it does this when i drive also unless it it wot can anyone help me fix this?

 

ive had this before and my conclusion is that your idle is messed up and needs to be recalibrated.

there is instructions in the helms manual on how to do this. however, i suggest my method, as ive tried that and it wasnt successful.

what i do is basically find the idle adjust screw and lower it all the way. this is whe nthe engine is warm btw. then slowly raise it from there. that will do a better job of getting the ecu to correct the idle better.

ppl will tell you your TPS and/or IACV is bad or needs replacement. i tried replacing hte IACV and it didnt do anything. and i dont think TPS goes bad nearly as much as ppl suggest.

the other thing you should make sure is if your coolant is properly bled with no air pockets. it matters to the IACV as it has coolant passing through it to know when the engine is warmed up.

 

i just got to looking the old intake was a hf-1 and the new one is a hf-2 was this a really bad mistake? and does that help anyone with finding the problem...still doing research across the web for differences in the two

 

actually that hf-1 and hf-2 has NOTHING to do with whether it was for a HF or not. All the Si manifolds have "HF" something stamped for sure.

there is a difference in the 88 manifold, it doesnt have some sensor, i forgot which.

thats really not your issue tho. you just need to reset your idle. thats what fixed it for me at least.

thats all the advice i have for you.