Mechanics

FUEL, TIMING, SPARK ?

1997 Pontiac Grand Am • 4 cylinder FWD •

Engine Performance problem 1997 Pontiac Grand Am 4 cyl Front Wheel Drive Automatic 200000 miles I recently rebuilt a Quad 4 engine in a 97 grand am because of blown pistons and head. I replaced all those internal parts (rings etc.) And it is hard to start. I checked timing (4 X'S) fuel and spark. I checked for vacuum leaks. The one thing that I noticed is that when I pull a vacuum line (any one) from the throttle body, it ran better. It was like it wasn't getting enough air. Then it wouldn't crank at all. I found out the fuel pump went out. Replaced that and it still would not start. Had it towed for diagnosis and they said I needed to change the computer, instrument cluster and maybe the the ignition switch. I replaced everything but the ignition switch so far. I'M TIRED! Now what would you suggest? I put too much into it to just let it go.
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Jkinard
March 8, 2011.



Time to go back to basics, re check valve timing, check compressions, check for any set fault codes, make sure that these are all OK, do not presumer thats something is good because it is new, that is a fatal error, let me know what you find.


Mhpautos
Mar 9, 2011.
O.K. I did a troubleshoot and I traced the problem to the fuel pump. When I turn the key on the ignition, I don't hear the "whirring" sound of the fuel pump. What do I do now? The Chilton and Haynes manuals are not clear to me on how to check the electric circuits and relays that lead to the fuel sending unit. They don't seem to specify for a 2.4 quad 4 I don't know the location of the fuel pump relay, etc. I would hate to have to take the gas tank out (again) if the fuel pump is not the problem.


Tiny
Jkinard
Apr 13, 2011.
O.K. I did a troubleshoot and I traced the problem to the fuel pump. When I turn the key on the ignition, I don't hear the "whirring" sound of the fuel pump. What do I do now? The Chilton and Haynes manuals are not clear to me on how to check the electric circuits and relays that lead to the fuel sending unit. They don't seem to specify for a 2.4 quad 4. I tested the f/p relay at the pink wire for power. Nothing. I couldn't locate the fuse for that component because the fuse diagram is unreadable. Where can I find a pic of the fuse diagram locating the fuel pump fuse? If I understand this right, power goes from the battery to the fuse box then to the component(F/P relay). I would hate to have to take the gas tank out (again) if the fuel pump is not the problem.


Tiny
Jkinard
Apr 28, 2011.
The engine fuse center is located next to the battery, C8 on the diagram. According to what I can find, the f/p fuse is in the convenience center under the dash. It is a yellow, 20Amp fuse, second from top left.
The maxifuses in the engine fuse block have a good-sized window you can look through to view the fusible conductor inside the fuse. Look for darkening and the lack of the small metal strip in the window to show a blown fuse.


Rivermikerat
Jun 7, 2011.