properly timed= hesitation

[korey_gunn]

When it's properly timed it bogs/hesitates...if I advance the timing it fixes the hesitation but the engine pings severely. I sprayed intake,hoses looking for leaks but found no apparent vacuum leaks.

[eurotiva]

What year will help us answer better. Carb/ EFI?

[korey_gunn]

im sry 89 efi 164,000 miles

[link5186]

Can we get a little bit more information? Did it just start acting up? After some repair? If you just did plugs and wires, make sure the 2 and 3 plug wires aren't mixed up on the distributor.

[korey_gunn]

when i got the car a few months ago my nephew [a mechanic] had to slightly advance the timing to rid the car of the hesitation. No timing light used.This was causing the pinging. So last weekend I asked him to retard the timing to fix the pinging. He did and it ran great for a week. Slowly the idle got rougher and more loopy, and after sitting @ a stop light on take off it would sputter for the 1st 10 feet or so, then clear up and run properly. Now I asked my other nephew [also a mechenic]to put his timing light on it and time it properly. We had a strange problem with timing light it didnt flash very often, only every 5-10 seconds. Anyway we manged to get it in time. Idle was a lil better but, it had a very bad bog/hesitation. We wound up adjusting it to a point when it pinged but had no hesitation.
air filter is clean,plugs,distributer cap,rotor,wires look good. Intake looks very clean. A few weeks ago I put lucas fuel system cleaner in tank, seemed to help the car run better..that was 3 tanks ago....I'm gonna put some seafoam in the tank tonight before work...Thats the history of the car fellas!

[crazyrog17]

The timing light not flashing indicates either a problem with the timing light or your ignition system.

Cap and rotor seems to be the place to start.

This also sounds like it could be a sticky VAF if it's intermittent.

[iceracerdude]

You disabled the computer before you set the timing right?
Check the tps adjustment with a meter so it's in sync with the vaf. After you do that take it for a ride and see how that does, Then put a pair of vice grips right on the return fuel line and then take it for a ride and see what that does.

[nitrofarm]

You disabled the computer before you set the timing right?
Check the tps adjustment with a meter so it's in sync with the vaf. After you do that take it for a ride and see how that does, Then put a pair of vice grips right on the return fuel line and then take it for a ride and see what that does.

What will that show when you block the return line? Jus wondering

[korey_gunn]

I disconnected the vacume lines and unpluged an electrical plug as per the instructions on a sticker under the hood.

[korey_gunn]

I noticed in the mornings I have little to no pinging.In the heat of the day pinging is allot worse! Is this normal?

[ericsmith32]

My 91 did the same thing. The PO advanced the timing belt by one tooth as a band-aid. Problem was the gas mpg has been terrible. Replaced the disty all together last week and gas mileage has went up by 4mpg. I see your close to Houston maybe one of the other Houston brotheren could loan you a disty and see what happens.

[JohnGunn]

I noticed in the mornings I have little to no pinging.In the heat of the day pinging is allot worse! Is this normal?

This behavior suggests that, in addition to the ping you have introduced by your improper timing, the engine is firing even before the ignition fires, from heat build up in the cylinders, called pre-ignition. Whenever a cylinder fires before it should there is stress on the engine which causes a build up of heat which causes the cylinder to fire even sooner causing even more heat. It is a destructive process and should be avoided.

My advice to you is to stop driving your car until the timing is returned to 10 degrees before TDC. Then address whatever problem exists at the proper timing. What you are doing is harming your car.

You should start by trying to observe if, during the bogging/hesitating you describe, the engine is misfiring. If so, your problem is with the ignition system. There the spark plugs are critical. It is not enough to look at them and say they look good. They should be replaced with a new set of NGK V-Power plugs. If that doesn't fix it move on to another part of the ignition system.

You may think that your problem is the bogging and hesitation, but what causes that may also be affecting your car's idle. Listen closely to that, and work to perfect the idle, before you move on to any running problems. What you do to fix the idle will probably have fixed the running problem as well.

Slow down. Read..., learn......, think.........; then act. As in so much of life, your greatest enemy is haste.

John Gunn
Coronado, CA

[blkfordsedan]

^^^^ I agree.

I don't think the timing is the real issue, it's just a parameter that is being used to solve the symptoms of the real problem. I would start with a complete tune up; plugs, wires, cap & rotor, fuel filter, clean the throttle body and clean the IAC. Even if it doesn't fix it, with the high miles it will be money well spent. Then set the timing at factory spec & see what you got.

[nitrofarm]

You disabled the computer before you set the timing right?
Check the tps adjustment with a meter so it's in sync with the vaf. After you do that take it for a ride and see how that does, Then put a pair of vice grips right on the return fuel line and then take it for a ride and see what that does.

This is very good advice for the symtoms you are describing.Jus my two cents I would do it before I spent any money on sea foam or fuel additives. Sounds like the VAF isnt doing its job all the time....

[korey_gunn]

Ok fellas I will return it to 10 degrees before TDC. and replace cap,rotor, and plugs!
I'm poor and was kinda hoping to avoid this. I dont want to harm the engine so it will be done. Thanks for all the help....Korey Gunn