89 firebird timing

[89firebirdv6]

hi
Does anyone know what the timing would be for a 89 firebird 2.8.
Car is idleing kinda rough with rpm jumping between 750-400 at lights.
After a while it gets annoying, so i thought I would check the timing.
Somebody took the label off so I dont know what the timing is suppose to be. The book says look on plate(mine is gone).

Anyways Thanks for the help
Thomas

[FormulaLT1]

The correct timing for your vehicle is 10 degrees before top dead center. Good luck Thomas and let us know how it turns out.
John

[Kurtdg19]

If the idling is rough you may have a vaccum leak or some faulty emissions components. Checkout your pcv valve and see if its starting to get plugged up. A sticking EGR valve can also cause irregular idling. Mines will go and check your air filter and see if its getting bad. You could also take off your hosing to the throttle body and spray some carb cleaner in the intake and remove some of that built up carbon.

[89firebirdv6]

thanks for all the info.
I tried setting the timing to 10 degrees. When i took the car out the next day it didn't have much power. So I adjusted it so it's not even on the plate, its like an inch and a half before the plate even begins. The car is faster than ever before but it stalls once in a while when i'm braking or if I gun it then just let the idle drop (but this is only once in a while not every time). Could that still be the vacuum stuff egr valve tha sort of thing. The air filter is a brand new K&N airfilter. plugs, cap, rotor, wires, fuel filter, air filter, ignition module underneath cap, synthetic oil, oil filter, battery, its all new and the thing still idles rough. any help would be appriciated.

Thanks alot,
Thomas

[Hypsi87]

Originally Posted by 89firebirdv6

thanks for all the info.
I tried setting the timing to 10 degrees. When i took the car out the next day it didn't have much power. So I adjusted it so it's not even on the plate, its like an inch and a half before the plate even begins. The car is faster than ever before but it stalls once in a while when i'm braking or if I gun it then just let the idle drop (but this is only once in a while not every time). Could that still be the vacuum stuff egr valve tha sort of thing. The air filter is a brand new K&N airfilter. plugs, cap, rotor, wires, fuel filter, air filter, ignition module underneath cap, synthetic oil, oil filter, battery, its all new and the thing still idles rough. any help would be appriciated.

Thanks alot,
Thomas

Might be an EGR related problem??? Thats about all my mind can think of at 7:30 in the morning

[FormulaLT1]

Does the check engine light ever come on or have you had the car scanned?

[89firebirdv6]

hi
yes the check engine light does come on one in a while for like a half a sec then it dissapears, in that half a second i have no power like it feels like i took my foot off the gas.
I did scan it and it says lean exhaust code 44.
but it only does it once in a while so thats why its wierd.
i put a vacuum gauge on it and it says late ign timing. but it said that before i changed the timing and it still says that so i dont know if it is accurate.

Anyways any help would be appriciated.

[Kurtdg19]

A code 44 could possibly be set off by a low voltage in the oxygen sensor. You might have some bad connections for the oxygen sensor.

Let me ask this, when you first start your engine up after a long leave does it run pretty strong? The O2 sensor doesn't produce any voltage when it is below operating temperature (about 600F). During this time your ECM will operate in an open loop mode, and it won't start using data from the 02 sensor unitl normal operating temp. If its only running rough after warmup, then this could be your problem.

It sounds like your 02 sensor is getting dirty or going bad. Check the connections and clean them if their are any signs of build up on them (or get a new one if you think its necessary). I would check that first, and then we can go from there.

[1991L98G92]

Did you disconnect the timing connector to adjust the timing? You should have a code 41 or 42 if you did. It is on the right side of the engine compartment near the hood hinge coming out of the wiring harness. Black single wire connector wire color is tan with a black stripe.
If you adjusted it with the connector connected, the timing will be retarded.

[hotrod_chevyz]

ROUGH IDLE:burnt valve,bad tuneup,compression low on cylinder x,worn cam or timing chain

check for a unsteady reading on a vaccum gauge,wich normally signals burnt or improperly adjusted valve,and do a compression testand compare for any sizable difference of compression between cylinders.if more than about 10% difference between holes,the block is just plain tired. Without knowing how many miles is on your car,it would be hard to determine what the problem may be.I think i would start with a fresh tuneup using the plugs and wires recommended from the factory ,and maybe some higher octane fuel.
Knowing if its a standard will also help.If it dies once in awhile,and performs poorly,it could be as simple as a partially clogged converter,or sloppy adjustments in the lifters.run a physical diagnostic(meaning compression test,fuel pressure test,timing chain test,valve adjustment*ect.)

[89firebirdv6]

hi

I did a tune up about a month ago
I changed everything air filter, fuel filter, plugs, wires, cap, rotor, battery, oil, filter, ignition module, egr valve, and oxygen sensor.
It is a automatic with 198,000 kms. the car seems to have plenty of power now but it still dies when i deselerate quickly, but if i put the car in neutral when stopping than the car is fine. vacuum tester was steady no needle movement.

Thanks Thomas

[hotrod_chevyz]

pcv valve,bad brake booster maybe..