Hi there I'm new to the forum and need help plz I have a 1990 honda accord It runs great when cold (closed loop) or above 2k rpm things I have done replaced ect sensor under dizzy that talks to ecm replaced upstream 02 sensor tried two different coils both were used out of wreckers thought so may still be coil new plugs cap and wires cleaned egr passages tested egr functions properly and set timing today 15 btdc if I ease into throttle very slowly it runs anything more than a slight throttle it stumbles until it backfires and dies help me please

 

Just updating my thread since this morning a new distributor and iacv have been installed still no difference

 

Did you pull the egr plugs and clean out all the egr ports ? There are something like 5 plugs.

 

I did all egr passages and valve are super clean

Just an update took off catalytic converter and still doing it cat I'd going back on now

 

Warm the car completely up. Disconnect the egr valve connector. When it throws a code for the egr valve, see if it still has the issue. Report back here.

 

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I'm leaning to a possible clogged cat now. Remove the oxygen sensor after disconnecting the connector and run the car without it and see if it runs better. Yes, it will throw a check engine code but it won't hurt anything. See if it runs better.

 

Ok sorry I'm taking so long just got off work pull electrical connection from egr after about five mins or so of driving an bogging it down and making it spit and sputter I got the cel to come on car ran way better but it was still there a little but way way better I also took cat off already and made no difference

 

I'm thinking your on to something with the egr valve but it's weird cause I cleaned passages and valve spotless could the valve itself be bad I revved the engine when still connected and could feel the valve open also opened it manually and the car almost died

 

When you cleaned the passages did you clean the tiny holes in the passages that lead down into the runners? Also I believe there are 5 plugs I believe or maybe 6, but it's more than 4. Been a while since I did them.

 

There's 6 plugs and yeah I cleaned the holes three were completely plugged

 

Update
Put egr delete and fuel filter on the car still stumbles under 2k

 

Have you checked fuel pressure? My 92 had a weak fuel pump, the engine would run but it would sputter badly with heavy throttle input. Mine was around 25 psi when running, needs to be 40.

 

Not yet don't have tool to do it but I can talk to a freind who might thanks for the advice I'll get back asap

 

So just an update still no fuel pressure check but I did a compression check an cyl 1 is at 150 psi cyl 2 is at 140 cyl 3 is at 95 and 4 is at 130? &#3 appears to be dead or contributing very little when unplugging each cylinder so now my question is could a dead cylinder cause my cat to misfire and stumble under load below 2k rpms but only when engine is warm??