Hello
I fixed the annoying gigantic backfire episode. But now my car has another problem that I just can't figure out.
When I was driving home happy to have fixed the back fire problem, I noticed little jerks as if it was between slowing down and accelerating when I tried to hold a speed. Then today I went ahead and put in all new vacuum lines. Every last one of them. After that, I started the car and it idled a little higher than it did before. Not sure why. Then I noticed a gigantic fuel leak. Took care of that too. Then I took it out for a spin to see how it ran. It was fine at first, but after not even 5 minutes of driving it did the jerky thing a little bit. Then after more driving it started doing it a lot, even when I was accelerating. Not while slowing down though. Seems to idle fine too. It feels like someone randomly turns off a cylinder. I put in some Fuel system cleaner. No difference. I checked all the injector power connections and voltage goes on and off fine. Checked all the spark plug wires. No difference. My fuel pressure is 53PSI steady. Oil pressure is ok too. Though I did notice a puff of black smoke from the exhaust when accelerating harsh. The timing is right too. I have no gas or vacuum leaks. I do however have cheapo iginition wires. They were fine before though. Spark plugs have only been in there since March or so. I am out of ideas. Somebody help! Sorry for the ramble...

<img src="confused.gif" border="0">

 

Oh and I forgot. When I turn the key to crank the engine to start, it cranks for a little then stops as if there was too much resistance for the starter to handle. Only does this every now and then. Also, a couple of time it would start and dies right off. Then retried and ran. <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />

 

As of today it has a clean new fuel filter and spark plugs. Is it better? NO! I'm running out of ideas. I will do a compression check just to be sure.

 

Hi,

From my experiece, this symptom would be caused by either temporary/intermitent fuel starvation, intermitent ignition problems, or vacuum leaks.

Fuel: you said that your fuel pump reads 53 psi steady, does that include while you are driving around, or only when you are idleing? Make sure it's good while you are driving. If it's fuel, I would suspect the fuel pump is having a problem (bad electrical connection?). I am afraid I don't know much about the 914's FI, but only the 2.0 had it right? Perhaps the FI brain is suspect, but I doubt that as it should most likely be totally working, or totally failed.

Ignition: Make sure your plug wires are in good shape, and make sure there are no spark leaks. Make sure your distributor is in good shape, but I doubt this would cause the problem you describe. Lastly perhaps your ignition box is bad. You mentioned in another post that you had a disconnected Crane box in the engine compartment, so assuming it works, you could hook it up in place of your current ignition box to see if things improve.

Vacuum: Check any hoses/boots that haven't checked already. Start the engine and spray around the junctions where vacuum lines meet the fittings, and the boots meet metal, with a can of carb cleaner (liberally). If you notice the engine run differently as you spray around vacuum fittings and such, your probably have a vac. leak.

Thats all that comes to mind for now. Let us know how it goes.

Abdul

 

I contaced Dave Darling from Pelican Parts and he said it might the the Throttle Position switch. So I disconnected it, but there was no difference. Except terrible acceleration and hesitation but it did the jumping thing again. I did a compression test. It turned out to be... well to say the least horrible. 7BAR on three and 6 Bar on the other. I think my engine is just flat out dieing. That's ok though, I have most of the parts to do a 6 conversion. Except for the engine. So once the car gets to germany I can drop the engine and fiddle with it all winter, maybe convert it to a six or something. Sigh. I have checked the iginition wires. They seem allright and the resistance is right. No vacuum leaks to speak of. Fuel pressure still way too high. Should be 29PSI and is 53. But it keeps it steady. That would maybe make it run rich but not unconstant. The valves are in adjustment too. The only thing I have not replaced is the breaker point. I'm gonna clean them up some with some sand paper and see if I notice a difference.
<img src="confused.gif" border="0">

 

You probably have a pinched fuel line, your symtoms describe a fuel starvation. Remove every rubber hose from the plastic lines and check the tips. Retighten the ones that are OK but not super hard. Set back the fuel pressure to 29 PSI since your actual pressure is flooding the engine at idle and contributes to bad performance.

Mihai

 

Any chance you've got rust in the gas tank, intermittently restricting flow?

 

how would I go about adjust the fuel pressure. Is it down on the fuel pressure regulator. There is a lenghty bolt that sticks out and a regular nut to hold it. I think that's what I have to do to adjust it. So I tried that, but besides terrible fuel leaks, accomplished nothing.