RE: IML: '83 EFI Stumbles

Good point, Bob- I was going to mention Chevron, as one of the brands that includes an injector cleaner in the mix.

Dick

From: mailing-list-owner@xxxxxxxxxxxxxxxx [mailto:mailing-list-owner@xxxxxxxxxxxxxxxx] On Behalf Of Wayne Michaels
Sent: Monday, July 17, 2006 7:36 AM
To: mailing-list@xxxxxxxxxxxxxxxx
Subject: Re: IML: '83 EFI Stumbles

Hi Leo and Dick, Another thought might be the potentiometer which sends a signal to the computer as to position of butterflies and how much fuel might be needed to make it perform?????????? Also My cars only run well on Chevron Supreme, If I put any other grade of fuel or brand of fuel the car doesn't run as well as it does on Chevron??????????Bob

----- Original Message -----

From: Dick Benjamin

To: mailing-list@xxxxxxxxxxxxxxxx

Cc: 'Wayne Michaels'

Sent: Monday, July 17, 2006 7:44 AM

Subject: RE: '83 EFI Stumbles

Welcome back, Leo;

I am glad you are well, stay that way!

I didn’t respond the first time you posted this, because I don’t really have anything better than a guess, and it isn’t even an educated guess, since I’ve never had this particular symptom to deal with, but as a shot in the dark, I would try running some fuel injector cleaner additive through with your next few tanks of gas – auto supply places carry it, and some fuel brands add it to their fuel. The reason I suggest this is that if there is some blockage in the fuel nozzles, or if the fuel pressure regulator valves are a bit sticky, or if the dye used in some brands of fuel has coated the optical parts in the fuel flow meter, making it a bit slow to respond, this stuff will slowly improve the situation, without having to take anything apart. It is sort of a magic bullet, but it takes a while to have effect.

If that has no effect, the next thing I would try is to take the control fuel pump apart to clean out any accumulated gunk in it, to make sure it is performing up to it’s best.

The only other thing I can think of that would make the fuel injection slow to respond, assuming the pressures are all within spec, is if someone has modified the power module amplifier that drives the control fuel pump in a way that lowers its frequency response. I can’t see why anyone would do that, and it would take a somewhat technical person to even know how to do that.

I’ve cc’d Bob Baker to see if he has anything to add to this – he has much more experience with these cars than I do, now.

Dick Benjamin

From: mailing-list-owner@xxxxxxxxxxxxxxxx [mailto:mailing-list-owner@xxxxxxxxxxxxxxxx] On Behalf Of Leo Heligas
Sent: Sunday, July 16, 2006 5:24 PM
To: Imperial Club
Subject: IML: '83 EFI Stumbles

Hi,

Now that i am able to post to the list, I have a problem for the EFI gurus. Mine starts fine and runs pretty good. However, If I push the throttle down too fast it will stumble and probably would quit if I kept the throttle down. If I push it down slowly it will take off just fine and rune fine until the next stop light and then all over again. Any ideas??

Leo H.