head scrather
 

Truck died while I was driving. ECMB fuse kept on popping. After some troubleshooting found it was the pump.

Put in a new delphi, and fired her up. ROUGH idle & bogging when trying to accelerate.

Ok, Checked fuel pressure. 13psi.
Disconnected the brown/Tan wire, set the timing to 0. Rough idle.
Checked TPS. OK.
Noticed after idling for a while SES lights
Checked codes. -33. Map checks out.
blocked off EGR. Same.
Noticed an injector not spraying right. Replaced. Same.
checked timing. Disconnecting the bypass causes her to stall. UGH!
Changed coil, wires, distributor was replaced over the summer, but replaced cap & rotor. Same.
Compression test 145-165 155 avg

Pulled ignition module and had it tested 3 times. Passed.

Broke out WinALDL that reads the computer . Everything looks good but running super rich, and map readings aren't where they should be.

Pulled plugs. Covered in SUIT! HMM... Replaced plugs.

Map is now running fine, probably all the suit.

So while watching the computer , I started advancing the timing. She's running much better, and disconnecting the bypass lets her idle for a little while before she stall. Still bogs and stalls while accelerating but better.

Plug isn't covered in suit.

Brought her to TDC, and pulled the cap. rotor is still pointing to the post on the ignition coil, but now the distributor is so advanced It's almost pointing to the #8 plug.

What am I missing?

Sounds like O2s or the wiring to them
 

Sounds to me like either the O2s are staying low or the wiring to them is screwed up giving the ECM a false lean indication that it is trying to over compensate for by fattening up the mixture.

FWIW, I had a 94 OBDI Camaro that burned through the signal wire to an O2 that never threw a code. But caused all kinds of running issues.

Wiring is easy to test with a scanner and a paper clip.

Re: head scrather
 

i would also suggest looking at the coolant temp sensor, if it is running rich...

Re: head scrather
 

:agree:

Re: head scrather
 

i third that. the 305 in my90 had a bad cts. it did exactly what your saying and eventually wouldnt start at all until it was left overnight.

Re: head scrather
 

I 4th that. Same here.

Re: head scrather
 

Ah heck ill 5th it :lol:

Re: head scrather
 

any update?

Re: head scrather
 

Sorry, Didn't receive any email notices asking for updates.

Finally figured it out. The after market distributor that was installed didn't have an index for the pickup coil. As soon as I flipped the connector she started right up.