Problems with 1990 Laser

[mistersq]

Hello..

1990 Plymouth Laser, 2.0 Turbo

1. Extreme hesitation on acceleration, have to pump the pedal to keep moving.
2. New remanufactured ECU.
3. Only one code that has since disappeared, code 14 (TPS)
4. RPM's go wild sometimes......0 to 6000 and back
5. Hold the accelerator steady and the engine ramps up and down (surges) by itself.
6. Used several cans of injector cleaner

What do you think?
Fuel filter (Replaced filter on Aug 8th)
Fuel Pump (how to test for this)
Bad ECU (How to test for this)
or ?

Thanks!

 

[gusu]

Fuel filters are cheap, if it could be a problem even if it isn't likely it should be changed.

If the ECU is in question take it out and check it, its quick and easy.

Don't forget to check your ECU harness because sometimes they get chopped up by previous owners.

 

[mysticstylez]

Sounds like you need to replace the tps to me. Go grab one from a junkyard or if you prefer new, local parts store. STM or DSMGraveyard may carry those too. Also, i'd go ahead and change that fuel filter. You will need an open ended wrench to get the high pressure fuel line loose from the old filter. Anyway, I'd start with the tps and a full tune up. It's also good to know your air/fuel ratio.

Spark Plugs
Plug Wires
Injector Cleaner
Air Filter

Good Luck!

 

[steve]

RPM's go wild sometimes

Explain.

 

[Achelea]

Does the RPMS bounce up and down at idle?

 

[DSM1G90]

..could still have an ECU issue, like a grounding issue inside the ECU got opened up somehow...

 

[mistersq]

Does the RPMS bounce up and down at idle?

No, at idle the RPM's are fairly steady.

Checking an ECU is not something I know how to do.

When I step on the accelerator nothing happens for a long time. I have to pump the pedal to get a response and even then, I get the engine racing and then dropping to idle.

This care was stored for years by my GF. I assume junk in the fuel is part of the problem.

 

[DSM1G90]

I assume junk in the fuel is part of the problem

.. and now guess what? that junk found its way to the fuel filter and is plugging up things.

Best to flush out the tank, put in new filter and away you go ..

Good luck-DSM

 

[mysticstylez]

Yes, and be sure to always use at least 93 octane.

 

[martindi]

Hello..

1990 Plymouth Laser, 2.0 Turbo

1. Extreme hesitation on acceleration, have to pump the pedal to keep moving.
2. New remanufactured ECU.
3. Only one code that has since disappeared, code 14 (TPS)
4. RPM's go wild sometimes

What do you think?
Fuel filter
Fuel Pump
Bad ECU
or ?

Thanks!

Have 1990 Laser N/T similar problem, found fuel supply line had big rusted hole in it and allowing junk to get in.

 

[mistersq]

Fuel filter has been changed and is not the issue.

Must be something else