1990gsx cranks but won't turn over....Please help

[maluman]

Hello, this is my first post I 've ont this board looking for the answers for ALONG

time(months) to see what the problem could be.

I am buying this car for a commuter car... i am in training for 7 months in ny and

going to buy it off of my good friend...now i will be able to diagnose the car since

i am at NY ..
Symptom...
The car ran about a month ago... the problems he was having was that while he was

in traffing it would stall on him.. then.. when he brought it home it would take a

while for him to start it.. like 10 to 15 cranks.... then eventually he could

not start it ....

here is some car info
1990 Eclipse GSX 150,000 miles,New battery,refurbished ecu,new fuel pump,new fuel

filter,new clutch,new plugs,new wires,new shocks,

Car will crank but will not start.
Checked Compression Good (About 160 all thru give or take 5psi)
Checked plugs Good
Checked wires Good
Checked Spark Good
Checked all hoses.. intake,intercooler,turbo,air filter,vacume etc.. all seem good
Checked ecu..... Brand new caps installed was refurbished..

so the next thing to check was the fuel system. i disconnected the fuel rail..( my

theory is that if i disconnect the rail we can see the injecters spit out fuel.....)

i had my buddy crank the car.. no fuel was spitting out... so then i thought maybe

there is no fuel.. so i disconnected the Fuel return line from the FPR.. and there

was fuel spewing out after we cranked... (thats when i thought that the FPR might be

bleeding pressure out)So i put my thumb at the return line outlet and cranked.. i

felt fuel push pressure against my finger but still there were not spitting out....

when i let go of the outlet.. the fuel spilled in the valley into the inlet of where

the injectors go and the car turned over and turned on for a sec or two.... so i

listened to the injector to here them tick.. all but one of them ticked... (1st one

on the drivers side)
So this test told me that the fuel pump is working.. the fuel filter is flowing fuel

freely, injectors are pulsing..
What i do not know is that What is the fuel pressure?, If the FPR is Bad and if its

bleeding pressure.. and if one injector can cause all of them not to work...

I checked to see if anyone experienced this before. and no one posted anything that

i can see.....
Please let me know what you think.. i am going to work on the car on sat and want to

buy the parts i need....

thanks in advance for all your help
George J.

 

[Froyd79]

Try a known good ecu. if same problem exists I then have no idea! I know a bad coolant temp sensor will cause it to need to be cranked alot to get started but if it just quit starting all together, I would have to say a bad ground or fuse somewhere. But the last car I worked on , took 10 cranks to start. Got a CEL for coolant temp. Replaced it, same condition. Pulled ecu out and the caps leaked on the board and ruined the board itself. needed a whole new ecu. Perfect ever since! I was just thinking if it was refurbished possibly the old caps ruined his board so new caps are not gonna work. Since it would be easy to do I would just swap in a known good ecu and go from there!

 

[BISHILVR]

Fuel pressure should be around 36-40 if I remember correctly.

 

[femmeDSM]

Have you checked resistance on the injector clips (should read 2-3 ohms)? Have you checked voltage at ECU Pin 51 (No. 1 Injector Pin on a 1990 ECU)? Should read ~12v at KOEO and will ground out each time the ECU tries to fire the injector. FYI, injector pins on the ECU are 51, 52, 60, and 61 (cyl 1, 2, 3, and 4 respectively).

How old is the gas in the tank? Drain it, clean the tank, an re-fill with fresh gas if necessary. A blockage in the gas tank near the pump WILL result in a no-start due to bad fuel pressure. Another source for incorrect fuel pressure is the fuel pump o-ring where the pump connects to the main fuel line coming out of the pump housing. Check the post-filter, pre-rail fuel pressure by means of a fuel pressure gauge. If you're low, inspect the tank, the pump (especially since it was freshly installed, a bad o-ring would be my guess here-would also explain the slow starts), and make sure the bolts on the filter were properly torqued.

Also - The Fuel Pressure Regulator maintains a pressure of 36.3 psi to the injectors.

If you can swap the ECU, I would recommend, just as a test. While you're at it, throw on another injector resistor pack just in case. These never go bad, but if you have a running donor car, it might be worth a try. Coolant Temp Sensor would be recommended as well. If this is bad, it's a $60 part from the dealer, but can be found cheaper.


If you were in Dallas, I would offer to come help you fix it.

good luck, though. let me know if you need any help.

 

[Old Mitsu Tech]

How old is the gas in the tank? Drain it, clean the tank, an re-fill with fresh gas if necessary. A blockage in the gas tank near the pump WILL result in a no-start due to bad fuel pressure.

Sounds like you speak from experience?

Anyway, here's what you need to run. Fuel, compression, spark at the right time. Any one of those missing and it won't run.

Compression you have. That leaves fuel and spark at the right time.

If you are absolutely sure about spark than that leaves fuel.

If you have the engine assembled, spray a little carb cleaner into the intake and let's see if it tries to run. Do this just to humor me.

If it tries to run, then you really do have 2 of the 3.

You have fuel pressure. That leaves getting it into the intake. This leaves injectors.

Use a test lite and probe the 12v wire on the injectors. Key on engine off you should light it on all 4 injectors. If it does that leaves your grounding circuit.

This is done by the pcm. At this point you can sub a "known good pcm" and see what happens. You can't test a pcm as it's full of integrated circuits.

If Steve happens by here he may elaborate as he can probably test and repair it if you need to have it done.

Good Luck

 

[femmeDSM]

Sounds like you speak from experience?

Who, me????