engine and drivetrain Idle Problems

[Utah02]

I recently replaced the fuel pump in my car. I have a fuel pump that ran upwards of 8 psi and caused horrible gas smell and consumption. So I switched to a Carter Low Pressure pump and have it mounted on the right rear shock tower above the tank. It sounds great and appears to be getting me better gas mileage but now I am having idling problems. I'm not sure if it's fuel pump related or just a coincidence that it went out the same day I put the fuel pump in. Anyways, some days I'll turn on the car and it will idle perfect. Right at about 850-900 rpms. Other days I'll turn it on and it will idle so low that it either will die or my foot on the gas is the only thing keeping it alive. Any help is greatly appreciated.

Thanks

Colby

[zinz]

What carb do you have?

[Utah02]

Weber 32/36 manual choke

[Mark92131]

Possibly there is contaminants in the fuel tank that are intermittently clogging the idle jet.  If you have a fuel filter between the pump and the carb, change it or add it, blow out the idle jet and see if your idle issues continue.

 

Others may have other suggestions.

 

Mark92131

[Simeon]

Can you (should you) mount a Carter pump higher than the fuel tank?

Edited October 20, 2015 by Simeon

[kbmb02]

Can you (should you) mount a Carter pump higher than the fuel tank?

 

I've seen the Carter 4070 mounted that way often ... it seems to have been the location of choice in most SCCA ITB race cars.

 

OP: you might consider re-checking the float level and needle/seat valve. -KB

[Mike Self]

Fuel filter in the system?  Have you checked it for crud?  Also, Webers don't like a lot of fuel pressure--IIRC 3 psi is about the limit.  Suggest checking the fuel pressure at the carb with a gauge and adding a pressure regulator if necessary.

 

And as an aside--a mechanical pump puts out the correct pressure without a regulator...and they're really long-lived...

 

mike

[airborne85]

Hi Colby

 

I hope that your idle issues go away and are an easy fix...

 

I think that the problems may have started the same day you guys (Utah Utes) beat Cal Bears.....This may be some sort of short term Cal Bear curse.  GO BEARS

 

ira

[Simeon]

I am with Ken on this one. If you believe it is related to the change of pump you need to check your needle valve and float. As a complete coincidence with the pump change (and therefore only a secondary consideration), how is your distributor? Are you sure that the advance weights are free and not sticking?