95 T/A

every time I try to start it, the tach jumps up and down between 0 and 1000 rpm, even though the motor never fires up to crank anywhere near that speed, and it doesn't start. I've checked for spark on plugs and coil, they're both fine. I swapped my ignition control module with a friends and it still wouldn't start. We've checked all grounds (battery to block, ignition ctrl module to frame, and battery to frame), still won't start. We took all the spark plugs out and cleaned them for carbon--no change. When I turn the key over, we get normal fuel pressure above 40 psi, but when it cranks, the gauge spazzes out between 20 and 50 or 60 psi, VERY quickly. This leads me to believe the PCM is telling the fuel pump to do crazy things. What on earth is the problem? All engine fuses remain intact.

 

Sounds like what my opti did when it was going out, i sat in the street for like 15min cranking it and it kept jumping up to like 600 RPM but not starting.

 

Yeah its typical for the fuel preshure to jump around till u get it started.
Is the motor turning over?
Are u getting spark at all the plugs?
Does it sputter at all? (almost start then stall)
Becasue if ur getting spark. fuel and air it should be starting, Unless ur got mechanele problmes

 

Okay, we got it started after a while with a massive amount of gas. It sputters and backfires like crazy, running super rich. The only way to keep it running is continuing to give it tons of gas. Any new opinions?

 

UPDATE:

I got it to start, though it ran pretty bad with backfiring. It threw codes:

CODE 42 - EST (Electronic Spark Timing) ground

CODE 36 - Hi-res fail

*Note on the 36 details:
36 Mass Air Flow (MAF) Sensor - burn off circuit problem
OR Transmission shift problem
OR Direct Ignition System (DIS) fault - extra or missing pulses in Electronic Spark Timing (EST) signal

Is something wrong in the EST system telling me that the opti is bad? I've checked all the connections on and near the ignition control module and coil--everything's tight. My main question is: is EST indicative of optispark problems?

 

Its not the maf, You got a bad opti spark

 

Yup you have a bad opti and the 42 is part of the knock sensor circuit if memory serves. Probably a broke or frayed wired to the knock Sensor.

High res is a dead give away you need an opti Tryied to ignore that one once...got left stranded

 

all these opti isues. What goes wrong with the OPTI ITSELF, and not just the cap/rotor?

 

many times it is OK. BUT alot of times the optics get dusted with Ozon and rust and can no longer read...and other times they bearing fails

 

Can't be cleaned, or just easier to replace?
I ask because mine is giving me issues I believe, and it only has maybe 20k on it, but I have a new MSD cap/rotor to put on. Don't want to do that if the whole thing is bad!
Sorry for the hijack!