I have an 89 iroc z convertible 305 tpi. I am having intermittent no start problems. I originally thought it was the fuel pump relay, I replaced the relay and it still sometimes won't start. Could this be the fuel pump going out or maybe the oil pressure sending unit or something else I am missing? Any help will be greatly appreciated.

 

What kind of no start? Turns over or not? Do you have VATs? Security light on or off? Does car start on next attempt or do you have to wait?

Good luck.

 

I can go to try to start the car and it will just crank over until the battery dies. I can go out another day and it starts perfectly normal. I have tried several times in one day and still no start. I am afraid to take the car any where for the fear of not getting home. The car does have the vats on it. I am getting no security codes or any other codes. It just won't start.

 

i have the same problem it will start one day and the next day itll try all day long until the batteris dead my problem is the fuel pump relay is in bad shape and there is also a short so the relay gets power sometimes and other times it dont so that could be your problem to

 

You can rule out the VATS system by turning the ignition on, and looking for a "security" light on the dash near the brake light, etc... If it illuminates, then there is a security issue. If not, it is something else.

You could check the fuel pressure the next time you have an issue. Attach a fuel pressure gauge to the fuel rail test fitting, it should be 42-47 at anything but idle.

Hope this helps.

 

Thanks for the replies I will check both and post how it goes. I appreciate the info.

 

Injectors, VATs, Fuel pump, or dist module.

 

the Fuel Pump relay works whether oil pressure is observed or not, as long as key is on 2 secs and/or cranking, or engine running. If the fuel relay fails, the oil pressure switch will power the Fuel Pump once 4 lbs oil pressure is sensed.

Has to be something else in the system, keep going out and trying it until it wont fire then try the fuel psi gauge on the rail and see where its at.

 

Something to read and try next time it wont start. Link from this site.
https://www.thirdgen.org/forums/tech...aro-5-0-a.html

 

Next time it won't start, put a noid light to see if the computer is pulsing the injectors and check the fuel pressure. If those are good, then check for spark.

It is very common for the dist module to go bad and have erratic behavior like you are seeing. Many parts stores can actually test the module if you bring it in.

When fuel pumps go out, they usually stay dead, since the issue is usually the brushes are worn. I have seen a good hit on the gas tank bring them back to life (for a short time), similar to a hammer on a bad starter.

 

Also when you turn the key on before cranking over the engine you can here the fuel pump kick on.

 

on mine we did a fuel pressure test with the key on and while trying to crank it so your saying its something other than a short?