1990 Chevrolet Lumina 2.5l Won't Friggin' Run.

[automan9482]

Can Anyone Help, Please!!!!!!!!!!!

I Am Dealing With A '90 Lumina 4 Dr. 2.5l That Will Not Run.
It Is Not Mine (belongs To My Mother), And It Has Only Run @ 1 Month Out Of The 5 It's Been Around. When She First Got The Car It Was Very Nice, 98k, Ran Great. 1st Day She Had It I Detailed It, And Cleaned The Engine, Taking Care To Avoid Electronics. As Soon As I Finished And Left The Car Wash, The Car Began Missing And Idling Very Rough. Drove It Around Awhile, And It Seemed To Dry Out And Run Better. Ever Since, It Has Not Been Right. It Will Run Fine Some Days, Not At All Others; It Has Hard Starting When Cold, Rough Idle, Bad Gas Mileage, Stalling,and Backfires. Also It Has An Intermittent "engine" Light, But It Doesn't Drop A Code.... 3 Seperate Mechanics Have Diagnosed This P.o.s. To The End, And (we) Have Replaced Plugs, Wires, Cat. Converter, Fuel Pump, Various Sensors, All To No Avail. Car Has Sat Idle For Past 2-3 Months Because It's Not Safe To Drive Even Around The Block. I've Brushed Up On This Car With A Couple Of Manuals, And Am Going To Try To Replace The Coil Packs (very Possible Therein Lies The Problem), Egr Valve, Since It's Not Connected To The Computer On This Car, And/or The Ecm.
I've Noticed From This Forum This Seems To Be An Incredibly Common Problem With These, 4 Banger Or V6.....
Also, Where The Hell Is The Ecm Located? I'm Going To Try And Snag One From A Junkyard If The Other 2 Don't Take Care Of It. This Car Is Junkyard Bound If It Isn't Fixed Soon, And Is Too Nice, Otherwise, To Have That Happen.
Does Anyone Have Any Other Suggestions????

[jeffcoslacker]

Module, on the back side of the motor. Lotsa trouble on those. Also the vacuum line to the MAP sensor on the firewall likes to collapse, drives the ECM crazy. Usually will be soft right near the sensor end of the hose.

[automan9482]

Thanks man. I will give it a shot.....

[jeffcoslacker]

Might wanna pull all the harness connectors apart and spry 'em with some WD-40, sometimes after getting wet they wont dry out and start to corrode. There should be at least a couple of big ones going into the firewall.

[jsgold]

My dad's 89 Olds also has the 2.5 motor. If yours is set up the same the coilpacks, ignition module and crank sensor are all bolted together and removed as one assy. Pain in the rear. My dad had trouble whenever it rained or was damp. Tried WD40, worked at times. If you are lucky it will be wiring connectors, but if that does not help remove the assy, have the ignition module tested at NAPA or Advance(could be weak) and replace the crank sensor while you have it out anyway. The crank sensor sits inside the engine block and will be cracked most likely. If you find ignition module is weak, suggest replacing coils as well, although this is up to you.

[automan9482]

thanks for the tip. I will surely try it out....

[Jonn]

Originally Posted by automan9482

thanks for the tip. I will surely try it out....

I just did this on a 91 - 2.5
crank sensor 18.00
Ign modual 80.00
2 coils 40.00
wires 28.00
plugs 8.00
you really cant beat it,add new plugs and wires and thats your whole ign. system replaced discounting sensors and computer.

[automan9482]

Well folks....just spent the whole weekend working on this damn thing. replaced the coil packs, ign. module, O2 sensor, and EGR valve. the car seems to run (Ever so)slightly better, but still chokes out/dies. the entire intake & TBI is full of carbon....Looked at the harness connections and vacuum lines; they're all fine. ECM is a recent factory rebuilt unit, so Im not suspecting it. Maybe I should though???
I didn't replace the CPS, because 1 mechanic who tried diagnosing it said they tested it and it wasn't faulty. Itll have to wait till next weekend when the insurance is reinstated, then Im going to dump some Lucas fuel system cleaner in it and try running it out on the freeway.... The parts I did change were definitely ready to be changed, so hopefully itll blow out some of that crap and be fixed........