HELP! - Engine Dies When Revved

[froggyrocket]

All -

Taking it to a mechanic on Friday. Will let you know what he finds.

Thx!

[froggyrocket]

Guys -

(sorry for the slow reply / computer crashed. Nothing a new hard drive couldn't fix. Joy....)

OK, I took my 88 to a mechanic to troubleshoot why it sometimes dies when stepping on the gas.

He said the accelerator pump diaphragm was in good condition...no rips, tears or holes.

He also looked at the inlet check valve to the accelerator pump like "johnmt" recommended but said it was clean.

He did have a question about the vacuum, specifically he wanted to know if vacuum should be present on both ports of the vacuum advance at idle? Looking at some specs on-line he found out that the top vacuum line is the idle and that with the bottom line unhooked and the engine running at idle with a vacuum gauge hooked to the lower port he was getting a bleed-through of about 6-8 inches of vacuum.

He wanted to know if that is normal.

Any ideas?

[froggyrocket]

Anyone -

Still occasionally having the same issue.

Same vacuum question as before: should vacuum be present on both ports of the vacuum advance at idle? The lower port is getting a bleed-through of about 6-8 inches of vacuum. My mechanic said he on-line spec info doesn't go back to 1988 so any help from the forum would be appreciated.

Hope I haven't offended anyone on this board by admitting I'm taking my Festiva to a mechanic. I'm eyeball deep in remodeling my home (3+ years) and don't have time to tear my Festiva apart myself.

[Mike McKown]

Anyone -

Still occasionally having the same issue.

Same vacuum question as before: should vacuum be present on both ports of the vacuum advance at idle? The lower port is getting a bleed-through of about 6-8 inches of vacuum. My mechanic said he on-line spec info doesn't go back to 1988 so any help from the forum would be appreciated.

Hope I haven't offended anyone on this board by admitting I'm taking my Festiva to a mechanic. I'm eyeball deep in remodeling my home (3+ years) and don't have time to tear my Festiva apart myself.

I have an 88 vacuum manual but not in front of me. I can look in day or two. In the meantime, I'll take a WAG and say NO, there should not be vacuum on both sides of your vacuum diaphragm at the same time. The nipple furtherest from the distributor should be spark advance, the nearest one, spark retard. Spark retard meaning retard the spark less than the initial timing setting on the crank pulley. The ONLY time I think there would be a need for spark RETARD is for some emmision reasons to increase combustion temperature and nothing to do with the engine running properly.

Unhook the the line and plug it and see what happens.

[froggyrocket]

Mike -

Thanks for replying! (I should have checked back sooner....sorry)

I'll tell my mechanic what you said about the vacuum next week when I take it in to him (he can't look at it before then).

If it's not too much of a hassle, can you confirm what you think about there not being vacuum on both sides of the vacuum diaphragm at the same time? His specs don't go back to 1988.

Had the same problem in early January. We then changed out the fuel pump, fuel filter (2nd time.....little bit of crud in it) and checked the gas tank like you mentioned before (he said it was actually pretty clean). Ran great up until yesterday. Same problem; dies above idle. (tho this AM it's running fine) Called my mechanic and he said he's starting to think it's electrical since it's intermittant and we've changed out almost everything related to fuel. Somebody above mentioned it might be the distributor?

Don't know if they're related or not, but prior to my two most recent episodes (early January and yesterday) my Festiva has been very hard to start; need to crank it at least a dozen times or more before it runs. Same thing today. This is driving me nuts.

As always, I'm open to ideas from anyone in the group.

I've had my Festiva 21 years/169K and do NOT want to part with it.

Thanks!

[JohnGunn]

Don't know if they're related or not, but prior to my two most recent episodes (early January and yesterday) my Festiva has been very hard to start; need to crank it at least a dozen times or more before it runs. Same thing today. This is driving me nuts.

To establish whether the problem is fuel or ignition do the following:

1. Buy a can of starter fluid.
2. As soon as you notice the starting problem, but before it actually starts, spray some of that fluid down into the throat of the carburetor.
3. If the car starts right up, the problem is in the fuel delivery system.
4. If nothing changes, the problem is related to the ignition.

If the latter is the case, even though I know you changed the plugs a year ago, my recent experience would suggest you do it again. I had an expensive set of Bosch Fusion plugs fail after only a few thousand miles in strange and inconsistent ways. Might be the best $10 you ever spent.

John Gunn
Coronado, CA

[froggyrocket]

John -

Hey thanks for the tip on the starter fluid. Makes sense.

Ditto for the suggestion on the spark plugs.

Taking my Festiva in tomorrow. Hopefully he'll find something. Running fine now. Not sure if that makes me smile or ticks me off since it's so intermittant....

If I had to take a guess I'd say it's fuel delivery/intermittant blockage in the fuel system. Electrical problems would be an "all the time" thing, wouldn't it?

Cheers!