Need help for the SC masters

markhaz

Registered User
Need help from the SC masters

First Off this Is Chuck Carroll not Mark. We are working over at marks house.

Well after a bizzilion tests I still cannot figure out my miss.
Here is what it does: at idle it has a noticable miss that sounds like a really lumpy cam. when driving on the road it misses continuously with a couple hickups every once and a while. During a hickup the tach drops about 400-500 rpm they picks back up to running rpm. On the tachat idle the miss in barely noticable.
It will more than likely hickup under any acceleration but not on every acceleration.

Here is what I have done: changed plug wires
Changed DIS
Changed Coil

Cam and crank sensor are less than 10000 miles old so I am shying away for those.

I have also pulled the plug wires one at a time and noticed somewhat of a difference on all cylinders. cylinder 3 is the most unnoticable.

I cannot run a cyliner balance test with a scanner due to my codes. which I have no idea how to fix the codes.

Codes are :
KOER
1. 13 Cannot control RPM during ER self test low RPM check
2. 91 HEGO circuit indicates system lean left side

KOEO
1. 95 Fuel Pump secondary circuit failed
2. 85 Canister Purge Circuit failure

I have tryed to check the signal from the crank and cam sensor with a test light but every time I tap into the wires the engine dies. What is the correct way of doing this?

Could this be a bad Fuel injector?
It does not sound like to me due to the random hickups that kills the motor.

I am starting to think about the computer its self?
I have an EEC tuner on the car and I have loaded my file onto that a couple of time thinking the tuner is bad but no luck.

I do not thisnk it is a pinched gasket or blown head gasket because I have good vaccum and no coolant in the oil with no coolant missing in the Radiator.

I have every bolt on imaginable and a equivilet to a stage 1 motor

Thanks for the input
Chuck
 
Last edited:
Fuel pressure

You need to verify that your fuel pressure is within band. It sounds like thats your proablem. On the driver's side there's a stem vlv like your tires on the fuel rale. The fuel pump is likely on it's way out.
 
Thanks

I did verify the plug wires. Besides I think I would have a backfiring problem if I had plug wires reversed.

I have to get the ford adapter for my FP guage, I seemed to have lost it. The pump is relitivly new but I have had one go bad before. I will check it tomarrow.


Chuck
 
A guy last week had a no start condition that was due to plug wires being messed up. I would have thought backfiring or at least bad misfiring with that. But apparently not always.

It might be your regulator too. While they typically fail open, leaking fuel, ya never know.
 
a simple thing

fuel filter ..that was a 50 hp bolt on for mine ...what a differents
.....your fuel pump sound normal ?...dave
 
Update

Well I have checked the Fuel Pressure. When I first hooked up the guage and turned the key on , but not starting the car, I got no Fuel pressure reading. When I started the car it climbed relitivly slowly to 40 PSI with the hose on and 42 PSI with the hose off, I have 42LB injectors.

I was under the asumption that I should have FP when I turn the key on?

Can this have something to do with my Purge canister curcuit code?

Or secondary FP curcuit failed, code?

I am assuming that this could have a hand in the other two codes as well.


How do I fix those codes?


Chuck
 
Fuel filter? Fuel Pump? Or Fuel regulator?

After messing around with my fuel pressure problem, I notice that when turning the car to the ON posistion the pressure QUICKLY shot up to 40lbs or so. You said it SLOWLY climbed? Did it drop after a few seconds? How long will it hold pressure?

If it holds pressure than I think it is NOT the regulator, or injectors. Maybe just fuel pump or the always under looked filter.

Need a fuel expert to jump in here......guys??.....
 
Re: Update

markhaz said:
Well..........When I first hooked up the guage and turned the key on , but not starting the car, I got no Fuel pressure reading.

Then again maybe be electrical? Might try and reset the fuel pump inertia switch....in trunk area....also isn't there a relay that runs these?
 
back to my computer

Well, when I initially hooked up the guage I turned the key on and nothing registered. So right there it seems I have a poblem.

On start up it slowly climbs to 40 psi, like 1-2 seconds to get there. I am thinking if the car is running then it should be under full pressure.

After shut off it dropped to around 35 psi after a couple of seconds, but I didn't stay to see if it leaked all the way down.

I have a stamped steel Holley AFPR.

I was told to run my FP at 42psi? Is that right with lucas 42lb injectors and a C+L maf with a purple sampling tube, and an EEC tuner?


Chuck
 
Seems to me that when you turn the key to the ON posistion, the fuel pump RELAY should energize the PUMP itself causing immediate pressure. However, if no signal is sent (when car is not started) to the relay within 2 seconds or so, the relay cuts the power off to the pump as the car is not running so it does not need fuel. It should STILL hold the pressure though.

Hook guage back up, turn key to ON posistion and see what it says. No fuel pressure pro, but 42 sounds like plenty, just odd that it takes 2 seconds to pump up. Have you tried running the car with guage hooked up? See if pressure falls when it does its "Hickup"?
 
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