Mechanics

TURNS OVER, BUT IT WON'T START

1995 Isuzu Trooper

Engine Performance problem
1995 Isuzu Trooper 6 cyl Four Wheel Drive Automatic 146000 miles

I drove it home the other night and then the next morning it would turn over, but didn't even " try" to start. I have spark to the plugs and I can hear the fuel pump working, but it acts like it isn't getting any fuel to the cylinders. Actually I determined that the fuel pump wasn't working so I replaced it and when the tank was down I checked at the pump and determined that I didn't have any voltage. I had already checked the fuse and relay so I thought that maybe the oil pressure switch might be cutting out the current to the fuel pump. I jumped the voltage and the pump worked, but still didn't start. I removed the jumper wire and reinserted the fuse and cranked the car to get the oil pressure up and the fuel pump works. Is there perhaps a fuel injector relay and or fuse? Maybe something to do with the emissions sensors? Was running fine before all of this. PS I haven't changed the timing belt and don't think the previous owner did either. I bought the car with 105,000 miles 2 years ago.
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Randy Wallis
March 25, 2010.



Hi
T belt should be replaced at60K. Does engine seem to turn over a little faster? If yes check to see if T belt is turning. Try spraying some carb cleaner into throttle body see if it fires.
Let me know
Thanks for donate

Docfixit
Mar 25, 2010.
It does seem to be turning over pretty fast, but I figured it was because there was no fuel to ignite. Is it maybe a lack of compression, hence the timing belt?

I tried the starting fluid in the intake and it didn't do anything. I will check the timing belt. Can I just try to look behind the plastic housing while someone cranks the engine?

Does this vehicle have any engine start lockouts like low fluids or perhaps something to do with the factory installed alarm system? Would a bad sensor or emission issue prevent it from even trying to start?

Thanks, Randy

Tiny
Randy Wallis
Mar 25, 2010.
Pretty sure you will find T belt to be problem

Docfixit
Mar 26, 2010.
Hey Bob, Ken and the crew, you were right on. I got the covers off and sure enough I should have changed that timing belt some miles ago. Several teeth are missing and the belt doesn't move at all. Neither cam shaft turned, but the crank did and so the pistons surely were moving as well.

My question now is how can I tell if there might be valve damage. I had tried to start the car several times, but of course it didn't even try to start so only the starter turned the engine over. It was running just fine the night before when I shut it off, it didn't die or anything so the RPMs were minimal what ever the starter turns over at.

Do you think I should just replace the belt and water pump and hope that the valves are okay. I'm guessing that short of removing the heads there is no other way to to know? Maybe the clearance is such that the piston doesn't go up high enough to touch the valves anyway? Also does this vehicle have intake valves since it is fuel injected or just exhaust valves?

Thanks for you help,
Randy

Tiny
Randy Wallis
Apr 5, 2010.
Hi
Engine is NOT an interference so valve damage should not have occured. Yes engine has intake and exhaust valves and water pump replacement is good to do at this time. Sending Timing marks


http://www.2carpros.com/forum/automotive_pictures/198357_Grafic_3_118.jpg


http://www.2carpros.com/forum/automotive_pictures/198357_Grafic_4_29.jpg


Will you be repairing yourself?

Docfixit
Apr 6, 2010.
I have the 3.2L SOHC and the timing marks are basically diametrically opposed. This diagram looks like the DOHC. And the information I have seems to indicate that it is an interference engine.

I think my best bet at this time is to reassemble with the new timing belt and see what happens. I have replaced the water pump and am doing the work myself. I will replace the timing belt and " give it a whirl" The belt I have has hash marks for the cams and it has a dotted hash mark that appears to be for the crankshaft, but in order to align the dots with the crank I have to reverse the belt and the writing is backwards, (right to left instead of left to right) The cams seem to line up with the marks either way.

Does it matter which way the belt is facing as long as everything is lined up correctly? Or is the belt direction oriented for some reason?

Thanks again for all your help, you've been great. I recommend this site to my friends and you can bet I will consult you before " changing unnecessary parts.&Quot;
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Tiny
Randy Wallis
Apr 7, 2010.
Marks for SOHC


http://www.2carpros.com/forum/automotive_pictures/198357_Graphic_437.jpg


Use pinch clip to hold belt


http://www.2carpros.com/forum/automotive_pictures/198357_Grafic_4_30.jpg


Adjust tensioner to this measurment


http://www.2carpros.com/forum/automotive_pictures/198357_Grafic_3_121.jpg


All my info says non interference

Docfixit
Apr 7, 2010.

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