1.7 Fuel Injection problem, Experts chime in! Options

[IronHillRestorations]

I've got a customer car here that's giving me some trouble.

To make a very long story as brief as possible, it's a '71 1.7 I've put new trigger points, ignition points, condenser (rotor & cap are like new), plugs look OK, injection tests out fine on my Ninefourtronics test set, fuel pressure is good when running bu it does leak down about 10 psi when you shut off the engine (I thought it should hold pressure), new vacuum lines (and yes I've double checked the routing to make sure it's correct). The engine has a different intake plenum (maybe out of an autostick 411??) and had no AAR, a cracked air intake elbow, bad vacuum lines and fuel lines, and some other problems. It is going to get the fuel pump relocated and new fuel lines, and a fuel tank cleaning or replacement.

The only issue I've had is after running it for a while the only way you can start it is with the throttle pedal to the floor. If you don't floor it, it will just crank and crank, It's suspicously like a vapor lock, but the car's got over 1/2 tank, and it's just not that warm here.

Otherwise it starts on the first or second crank by just turning the key. The engine is tired and close to the end of it's current service life, but this is kind of strange. I have the mixture pot on the ECU set fairly lean, as it seems to run best there.

The only other issue I've got is that the idle speed bypass screw is really at the end of the limit to get it to the correct idle speed, but my guess is this could be the fact that the engine is weak.

If you have a good opinion on this, I'll take it. Oh and no it's not my car so don't tell me to chunk the FI! (IMG:style_emoticons/default/smile.gif)

[toon1]

Hi Perry. Advance weights stuck or head temp sensor failing! (maybe?)

Hi Perry. Advance weights stuck or head temp sensor failing! (maybe?)

(IMG:style_emoticons/default/agree.gif)

Clean the distributor plates.

Rich

Is there a lack of power? what rpm does it idle at? if the weights where stuck A: there would be a huge lack of power. B: the rpm's would not come down after a drive. the weights would be out, advancing the timing, keeping the rpm's up.

If you need to keep the pedal to the floor after a drive and the motor is warm, the engine needs more air for ignition, sounds like leaky injectors. A motor does not need a whole lot of fuel to start after a drive with the engine warm. there is a fine line between starting back up and flooding.

eaisiest way to tell is to run the car and pull the injectors right after and check the tip for fuel leaking.
OR

Repeat the hard start scenrario without depressing the pedal, before the car starts check the plug see if it's wet or smells of excess fuel.

If it fires ok cold ( if the injectors are leaky) the fuel has had enough time to evaporate and the pressure has bled off the sys. so there is no extra fuel and the sys. is back to normal.

you would be supprised what can get past a fuel filter. I found small rust flakes coming out of my injectors that where bypassing the filter.

It does not take much to stick open and injector.

Keith

[dr914@autoatlanta.com]

Hi Perry. Advance weights stuck or head temp sensor failing! (maybe?)

Hi Perry. Advance weights stuck or head temp sensor failing! (maybe?)

(IMG:style_emoticons/default/agree.gif)

Clean the distributor plates.

Rich

Is there a lack of power? what rpm does it idle at? if the weights where stuck A: there would be a huge lack of power. B: the rpm's would not come down after a drive. the weights would be out, advancing the timing, keeping the rpm's up.

If you need to keep the pedal to the floor after a drive and the motor is warm, the engine needs more air for ignition, sounds like leaky injectors. A motor does not need a whole lot of fuel to start after a drive with the engine warm. there is a fine line between starting back up and flooding.

eaisiest way to tell is to run the car and pull the injectors right after and check the tip for fuel leaking.
OR

Repeat the hard start scenrario without depressing the pedal, before the car starts check the plug see if it's wet or smells of excess fuel.

If it fires ok cold ( if the injectors are leaky) the fuel has had enough time to evaporate and the pressure has bled off the sys. so there is no extra fuel and the sys. is back to normal.

you would be supprised what can get past a fuel filter. I found small rust flakes coming out of my injectors that where bypassing the filter.

It does not take much to stick open and injector.

Keith

CLAIRIFICATION:

If stuck slightly (meaning the distributor rotor will not spring back), the timing will not be retarded enough for an easy startup