1G 1990 Laser RS Fuel Cut Issues

[Jendron Eves]

1990 Laser RS

Looking for some input on some boost/fuel issues on cold(ish). If I cold start and attempt to rev/drive it, car wont go over 2.5k-3k RPM, massive fuel cut when parked. Doesn't build boost obviously. Idles pretty poorly too, can hear small misfires and sometimes drops RPMs and sounds like it wants to die (never does).
If I try to drive it, it bucks like bad, I can smell it dumping fuel, completely undriveable unless you slowly build speed under 2k RPM.

The kicker: If I let it idle for 10-15 mins, then go and drive it, it drives completely fine and strong. Builds boost, never fuel cuts, even idles well at stoplights etc.
Seemingly only causes issues on cold starts (very bad and takes a long time), or if I leave it off for more than a minute or two, it gets bad again but only for a couple miles. Not as bad, a bit more driveable but will buck at like 3k+

So far I've checked for boost leaks at all the lines, I can't hear anything at gaskets or lines (like I said it drives pretty damn well once it's warm). I've swapped the MAF and the Coolant temp sensor, same issue. Also changed plugs and fuel filter, ran injector cleaner as well. EGR has been disabled by prior owner, not sure if a proper blockoff plate was installed (i'd bet not). Fuel pressure regulator is looped to intake manifold. Only emmisions active is purge valve/canister.

My next plans are to take apart TB (of course it's a 1990 TB fml) and Intake manifold and get new gaskets. I'm just confused as to why it only throws issues when "cold", and drives almost perfect the rest of the time.

Let me know any thoughts or if you have experience with same issue.

I've searched quite a few different variations of my issues and can't seem to find something that matches my issue.

 

[pauleyman]

Please post a profile post. All we know about the car other than the above post is that it's a 90 laser.

What have you checked?
mechanical timing?
spark wires?
Did you actually boost test?
fuel pressure?
compression?
leakdown?
ignition timing?
Any logs if possible?
What tests have you performed?
Help us help you.

The ECUs job is to provide fuel for a measured amount of air and adjust ignition timing for whatever conditions and feedback the ECU receives. That being said this problem could be any number of sensor or wire related issues associated with what feeds data to the ECU OR mechanic problems such as timing belt, fuel pump etc etc.

So, what have you checked? Do you have any sort of software to read what ECU sees? Did that happen out of the blue? After a repair? Did it always do it?
What changed?
I would start with at least a though visual of the harness and connectors of sensors etc including the coolant sensor even though you just replaced it.