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Trouble starting

Hello community! I am very new and I hope I post this the correct way.
I own a 91 Olds Cutlass Ciera.
So to be blunt my car will not start. Correction it will not start unless I pump the gas pedal.
I have changed the fuel pump relay, fuel pump, and fuel filter. The starter cranks and I have no loss of voltage on the battery while the engine cranks. Once I pump the gas pedal it turns over like a champ and runs good. I just had the car smogged and passed with flying colors.

Does anyone have any sugestions? Thank you.

Do you have a fuel pressure gauge?

I suggest that you continue to give it a pump to start it. The FI is programmed to inject a little gas when you hit the starter either through the main injectors or through a separate cold start injector. You are not getting this initial shot of fuel, but the cost to fix probably won’t be worth it since you have an effective workaround.

Just think, if a car thief does not know this, it will be less likely that he can steal your car now.

Db4690; I don’t own a fuel pressure gauge but did rent one from the parts store. When I turn the key on it pressured up to 40+ psi before I cranked it and holds pressure too… I thought that same issue as well.

Keith: I just worry about killing the starter.

Your problem might be with the Idle Air Control valve.

When you normally start the engine with your foot off the accelerator, the IAC valve opens slightly to allow air into the engine. If the IAC valve doesn’t do this the engine gets no air and won’t start. But as soon as you step on the accelerator and open the throttle plate, the engine all of sudden gets this air and it starts.

Tester

Thanks tester. I will look it up in the service manual.

Tester: The IAC was changed only 2 years ago.

Does any one think this could be a bad MAF? It looks like my engine is running rich. I could even smell fuel when i removed the air filter.

Your engine doesn’t have a Mass Air Flow sensor. It does have a Manifold Abolute Pressure sensor. And that could be the problem. The MAP sensor replaced the vacuum advance and the accelerator pump that were found on carburated engines before they were switched over to fuel injection. But I don’t think that’s the problem.

Start the engine and let idle for a minute and shut the engine off. Remove the vacuum hose from the fuel pressure regulator. If gas leaks out of this connection, the regulator is leaking and requires replacing.

Tester

thanks Tester I will try this.

Your pressure test indicates the regulator is OK, but since it is easy to check, check it. When you tested the fuel pressure, did you turn off the engine and see if the pressure bled off over a few minutes (or hours)? You could have a leaking injector that is flooding the engine.

There is a backflow preventer possibly or leaking injector, turn the ignition key to on for 20 seconds before trying to start the car. if that helps let us know, especially if you have ears good enough to hear the fuel pump running.

It sounds like a simple cold start problem. Assuming all the routine maintenance is up to date. Timing and idle speed are at spec.

This should be fixable without too much expense. And it looks like you’ve ruled out the fuel pump and if you follow @Tester 's suggestion above and no fuel leaks out, the fuel pressure regulator as well, so that’s good.

Since you passed emissions with no issues, I doubt the problem is the MAP.

It could be the IAC, but since you say that part is fairly new, more likely if the IAC were the problem, it would be the control to the IAC, not the IAC itself. The IAC simply does the same thing you do when you press of the gas pedal, to increase the idle while the engine is cold. It is controlled by the coolant temp. On a 91 I’d guess though that the coolant flows right through the IAC to heat it up, and it works sort of like a mechanic thermostat, so there is no ECM or separate coolant sensor and vacuum line involved w/the IAC. (You should verify that by the repair manual specific for your car. Sometimes the IAC is called something else, like the “air valve”). Checking you coolant level is up to spec is worthwhile in any event. And checking that the engine coolant sensor is working is a good idea too. (Note: This is often not the same thing as what is used to measure the coolant temp shown on the dashboard guage, so your dashboard guage may show the coolant temp is normal, but the coolant temp sensor used by the engine could be on the fritz.)

My first guess though for the cause of your grief is the same as mentioned in one of the first posts above, the cold start injector. Either it isn’t working, or more likley, it isn’t getting the signal it is supposed to be getting during the Cranking phase. Look in your repair manual on how to check the cold start injector. (Newer cars don’t use cold start injectors, and yours may not have one either, so check your manual. In that case it would be a problem with the coolant temp sensor or the ECM not properly upping the fuel flow via the existing injectors during cranking).