New to forum, have a stock 90 i-roc, TPI 305 planning to drop in 350, my 305 won't start, i have a good spark at the plugs new spark plugs anybody know what gives////

 

welp, if ya got a starter turning and a sparky sparkin, then that just leaves a fuel delivery problem. i dont think you have a cold start injector, so don't worry about that. maybe check the fuel pump, aquier a fuel pressure gauage and tap it in-line into the passangers side fuel rail, and check the pressure, if ya got pressure, then check the injectors for fireing. also pull the codes and post them here

if you dont know how to pull the codes, gather up a paper clip and a pad and paper, and head on over to the tech articles on this site, and read it carefully...

good luck! and welcome to the board

Steve

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86 Firebird, LG4, t-tops, 2.73 open rear, SLP 3 inch cat back exhaust, catco cat.

Gonna be sellin the 86 in the spring to hopefully get an 88-92 formula 350, and supercharge it!! (amoung some other sweet mods)

My Webpage- Battle of the birds, My own Thirdgen Page, still under construction, http://www.geocities.com/soares711/index.htm

88 Firebird Formula- deseased 2/9/99- 305 TPI, SLP 3 inch exhaust, SLP Intake runners, SLP cam, 3.45 BW disc brake posi, WS6, NOS, and all that good stuff, 13.8 on the motor, 12.89 on NOS and slicks! Hit by what else!?!? a FORD EXPLORER!!!!!!

 

Army,

Welcome aboard! It's not the greatest way to start your experience with ThrdGen.org, but you'll get first-hand knowledge in just how helpful the board can be. It would be better if you were asking about a modification or planned build, but since you're dead in your tracks, we'll get you going again before you start your next improvement project.

FB is correct - you've got spark, and you are apparently cranking. With a TPI, if it's been twenty seconds since the ignition was on, as soon as you turn on the ignition, you should be able to hear the fuel pump run for about two seconds. This should build pressure in the injector rails. On the right rail near the rear of the intake plenum is a Schrader valve used to test fuel pressure. Remove the cap from the valve and slightly depress the center core stem (like a tire valve core). You should get a spray of fuel from the fitting.



If you have fuel pressure there, the pump can be assumed to be operating and the injectors are not firing. If there is no fuel pressure at the fitting, or if you don't hear the pump run, you'll need to check the fuse to the fuel pump. The fuse is located near the battery on many ThirdGens.



If the fuse is O.K., the fuel pump relay may have failed. If the relay fails there is a failsafe built into the system that will operate the pump. The pump will get power through the auxilliary oil pressure switch, but you must crank the engine long enough to create 7-10 PSIG of oil pressure before the switch will close causing the pump to run.



Report back with your findings, and we'll be here in numbers to get you going again.

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Later,
Vader
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"Make Me Bad"
Adobe Acrobat Reader 4.0

 

IF after all that... you have spark.. you have fuel.. fuses are good.. the next possibility may be your timing chain.

Whenever I have had a car that would not start when I had spark and fuel, it has usually turned out to be the timing chain stretched and jumped a couple of teeth.

But, DO listen for that fuel pump for the first 2 seconds when you first turn on the key. My fuel pump recently went and that was my clue that it was the fuel pump.

 

I had the same problem this summer. I noticed that my security light stopped coming on though when cranking the engine. It got spark but no fuel. The computer was cutting off all the fuel because the little wires in the lock cylinder for the security were broken. I had the Vats(vehicle anti-theft system) removed from my prom though. I could have gotten the wires fixed though but that would have required more work.

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'89 Formula 383 TPI