my car is a 91 crx hf, i have a y7 block and z6 head and intake manifold, p28 ecu. the symptons is the car revs from 1k rpms to 1.5k rpms and sometimes it gets lower like 600rpms to 900rpms and when i start out it hesitates a little then drive normal. there is a slight miss or loss of power around 3-4k rpm sometimes. engine check light is on after i reset it and is throwing #3. MAP sensor?

 

i'm trying to post the entire diagnosis procedure for code #3 (map sensor failure), its in pdf format, but I don't know how too.

basically of the three wire going to the sensor, one sould have 5 volts, one should be grounded, and the other is the signal wire. that one is the variable, at operating temp at idle, it should be around .8v to 1.0v. any higher than 1.0v is an indication of a vacuum leak, or burnt valves or incorrect valve lash.

but I would probably start off by just trying another sensor if you can find one.

let us know what you find.

 

anyone else have this problem?

 

look in the faqs next time, theres a link for CEL codes and idling issues

FAQ https://honda-tech.com/zerothread/1508680

CEL codes https://honda-tech.com/zerothread?id=468260&page=3

It sounds like your problem is the FITV or IACV, but make sure its not a vacuum leak.

Idling problems https://honda-tech.com/zerothread?id=2153910