David Fite

So here's the story:

Bought the car last fall, had the timing and everything fixed by a mechanic, car ran great (other than leaks and brake problems...)

I parked it for the winter since I needed to fix the leaks and brakes. One of the things I fixed (yesterday) was the fuel inlet/outlets were both leaking on the TBI. That involved taking the throttle body off, putting the little plastic washers on, and putting it all back together. Once I did that, I tried to start it, and didn't work. It turns over, sprays fuel from the injectors, and I tested 1 spark plug and got spark onto my screwdriver. It just won't fire up.

What all could have happened just sitting there? Could the plugs be fouled or something? I have a new set but haven't put them in yet, I figured since I've not touched anything at all other than the TBI, there must be some other explanation. I'm gonna re-check all my connections tonight, maybe there's some wire or something that I missed or came loose or something.

Any ideas? I can work on stuff but don't have a lot of experience when dealing with timing, spark, that kinda stuff. Mostly changing brakes, stereos, stuff like that.

Ikes 91Z

iTrader: (1)

You might be getting fuel, but what is the fuel pressure? Might not be getting enough. Changing the plugs like you mentioned wouldn't hurt either.

ASE doc

One question, did the car start before you resealed the fuel fittings? A quick visual check can help verify fuel pressure. The injectors should produce a conical spray that pretty well fills the diameter of each throttle bore. If the spray from the injectors is weak, that's a sign of low pressure. Common problem was the spring in the regulator, which is part of the throttle body. The spring rusts and finally crumbles and you lose pressure.

Check spark using a KV tester at 40KV, or you can use a screwdriver inserted into the plug end of the wire. Hold the screwdriver 1 inch away from a good engine ground while a helper cranks the engine. Test at a couple of wires. The spark should jump a 1 inch gap. If not, you may have a weak coil or leaking wires.

Testing spark with a spark plug laid against engine ground isn't good enough. Just because spark will jump the plug gap sitting in open air, doesn't mean it will combust the rich mixture in a cold wet cylinder. That's why we need to verify KV potential.

Double check your work. To pull the TB, you had to disconnect the TPS, and some vacuum lines. Make sure that the connections are good. Check the TPS connector for bent pins. Make sure the vacuum line to the MAP sensor is all good.

EDIT: Add IAC to the list of things to re check.

Vanilla Ice

Could be you need new fuel. Drain completely and refill.

David Fite

Well it started up yesterday. I put fuel in it when it was not starting, but I guess it could be that the fuel gauge isn't working, then I put fuel in, but it was flooded, and now it's working fine. Who knows.

There's a vacuum line that wasn't hooked up originally that I fixed in the middle of all this. I unhooked it before I started it yesterday just to see what would happen and it fired right up. I hooked it back up, and it still fires right up. So I don't think that was an issue, but FYI.

Other possible answers are that I have a loose connection of some type and by going over all of them yesterday I just happened to get a better connection this time around. Thanks for the replies though, I will keep those in mind if it does it again.

ASE doc

Cool. Maybe a fresh tank of fuel with a bottle of fuel system dryer would be a good idea. A new fuel filter should go along with that. Also, worn plugs, old wires and dist cap and rotor make an engine more sensitive to fueling issues. A full tune up with good quality parts goes a long way towards reliability.

David Fite

Thanks. It actually got new wires last fall. I have new plugs just waiting for time and weather to install. Lots of little projects to do, plus it needs brakes and brake lines, and has a leak (either RMS or o-ring...). Life has just gotten in the way so haven't been able to spend much time on it. Little by little...