The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support JNZ Tuning
Please Support Morrison Fabrication

1G Barn find won't start

rvllaser

Probationary Member
6
5
Sep 5, 2022
Ozark, Alabama
We have a 1991 Laser 1.8 FWD 5 speed. Car was parked 17 years ago with a bad fuel pump. We removed, cleaned, and sealed gas tank and installed new fuel pump and filter along with new fuel injectors. We have fuel at the injectors and spark at the spark plugs which appear to be in good condition. The engine cranks but will not start.

Cold compression test resulted in 40psi per cylinder - obviously way low. Adding oil to the cylinders raised the compression to 45psi.

Any ideas on what to test next before we have to break into the engine? The service manual says it could be stuck valves or a leaking gasket. We removed the valve cover and the rollers appear to move properly and their is fresh oil being moved into the assembly.

I'm at a loss and could use some help. Thanks.
 

steve

DSM Wiseman
14,861
1,719
Feb 3, 2002
Boulder, Colorado
At this point a leakdown test should help you with where the cylinder pressure is going.

This may give you additional ideas. https://www.dsmtuners.com/threads/how-to-diagnose-a-no-start.217951/

Make sure than when you turn the ignition on the CEL turns on for 5 seconds and then turns off. If it doesn't the ECU isn't functioning and it's not going to start even once you get the compression back up.
 

wparks

10+ Year Contributor
62
23
Mar 19, 2012
Fort Collins, Colorado
Check the timing belt. Since the compression is super low, does not increase when you add oil (not rings) and is more or less equal across cylinders (not head gasket or a single stuck valve, not likely ANY stuck valves if you get SOME compression) it almost certainly has to be valve timing. You can rotate the crankshaft with a ratchet on the crank pulley bolt until the timing mark on the crank pulley is at top dead center (0 degrees or "T") and check the timing mark position on the cam pulley. I bet it's off a number of teeth.

I should have mentioned that the crank pulley will be at it's timing mark twice in a 4 stroke cycle, and the timing gear will be at it's timing mark only once in the 4 stroke cycle- So if the crank pulley is at it's mark and you don't see the cam gear timing mark, rotate the engine one more turn back to the crank pulley timing mark at 0 degrees and the cam gear mark will either be spot on or a few teeth off, then you will know. Please let us know what you find.
 

rvllaser

Probationary Member
6
5
Sep 5, 2022
Ozark, Alabama
At this point a leakdown test should help you with where the cylinder pressure is going.

This may give you additional ideas. https://www.dsmtuners.com/threads/how-to-diagnose-a-no-start.217951/

Make sure than when you turn the ignition on the CEL turns on for 5 seconds and then turns off. If it doesn't the ECU isn't functioning and it's not going to start even once you get the compression back up.
CEL light functions normally. On for 5 seconds then off. I’ve read through the no start diagnostic and will see if I can get a leak down tester or have it done. Just surprised that the pressure is so low across all cylinders. Thanks

I should have mentioned that the crank pulley will be at it's timing mark twice in a 4 stroke cycle, and the timing gear will be at it's timing mark only once in the 4 stroke cycle- So if the crank pulley is at it's mark and you don't see the cam gear timing mark, rotate the engine one more turn back to the crank pulley timing mark at 0 degrees and the cam gear mark will either be spot on or a few teeth off, then you will know. Please let us know what you find.
Thanks. I will check timing and let you know what I find.
 

rvllaser

Probationary Member
6
5
Sep 5, 2022
Ozark, Alabama
You must be logged in to view this image or video.

Is this indentation on the crankshaft gear considered the timing mark? I see nothing else on the gear. The repair manual shows it as a triangle. If this is the timing mark then our engine is way off on timing. Thanks.
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Top