Hey guys. So I've been having a problem with my 91 accord. When the car has been running for a while (over 15 mins usually) it would start to have small "stutters" with the RPM's and when you go to push on the gas from a full stop the RPM's will drop then shoot back up. Sometimes the engine will even cut out before the RPMs have a chance to come back up.

I've also noticed while driving (past that 15 min mark) that I'm getting fewer RPMs in general. For example, when I'm cruising at 60kmh I usually get to almost 2000RPMs. But past that 15min mark or when I start to notice the other signs of trouble (RPM drop after pushing on the gas at a full stop) then I usually get around 2500/2600RPMs.

I do also have a check engine light and a cel code of CYP 9 - Cylinder sensor.

Does anyone know what this might be? I've talked to a friend and they though it might be my timing.

 

CYP sensor is one of the 3 timing sensors inside the distributor. Look for dirty/loose/corroded connections in the wiring harness plug at the distributor.

I don't think it's as simple as adjusting the spark timing.

 

Don't take this the wrong way....but the computer in the car, the ECU, is trying to tell you what the issue is. Why not listen to it?

 

replace the distributor and retest....

 

I had this fault on 94 EX and after replacing distributor found the ECM was the problem.

Measure distributor sensor resistance against spec (?). If sensor resistance is zero or infinite, then a new distributor is required. If it measures w/i spec, suggest further checking resistance at ECM connector (to rule out wiring fault). If resistance is again OK, then replace ECM (used are readily available).

good luck

 

did you have the exact same issues?

I'll test it when I can get my hands on a multimeter. And your suggesting replacing the ecm even if the resistance is okay?

The problems started a couple of months after I replaced the distributor.

 

It either ran poorly or failed to start.

good luck

 

What Tex said was to measure the sensor resistance, then measure it again from the ECU plug to check the wiring. If it's bad either way, you found a problem to fix.

If the sensor and the wiring are OK, then what's left is the ECU.

 

Alright. Replaced the distributor with a new one and everything seams to be working well again. Check engine light is off and all is good. Thank you everyone for the help

 

Good to hear.....like it when we know the end of the story and it has a good ending.