Time for a new coil pack, etc?

[litdog83z]

When I hook a timing light up to cylinders 1, 3, or 5 (driver's side, rear bank of plugs on the coil pack) it'll flash slow a couple times then a short burst of fast flashes at idle.

If i hook i up to the passenger side (2, 4, 6, front bank of plugs on coil pack) cylinders it flashes consistent and normal except for the occasional miss every few seconds.

This is all at idle, and only on the driver's side wires. The idle isn't as nice and smooth as i'd like, and it smells a bit rich (might be unrelated). Should I try a new coil pack/ignition module/etc? 163k miles on the engine, and I have no record of them ever being replaced.

Thanks

 

[Hacksaw]

First, how old are the spark plugs? They can also tell you if it's running rich.

Plug wires can also go bad & arc to ground, but that will cause rough running all the time.

Spark voltage needs go up under load & boost. If it's ok at cruise & WOT, then look for the EGR valve being stuck slightly open, and check the IAC adjustment. I'm guessing it's not using tons of oil, or has other obvious problems.

Do you get any ECM codes during testing it? Rough idle can also be dirty fuel injectors.

-Mike H.

 

[litdog83z]

IAC is set right, plugs looked fine last i checked, i doubt it's just all 3 of the driver's side plug wires and not any other ones arcing.

I'm using a power plate for the stock plenum without the EGR hole drilled, so the EGR should be non-functional anyway, so that counts that out.

Injectors look as old as the car, those are about to be replaced with 50#s, because they leak down most of the pressure in 20-30 minutes.

No ECM codes.

My timing light is just flashing really erratically when hooked up to any plug wire on the driver's side, but flashes normal on the passenger side, so i'm thinking there's something wrong with the coil pack/module and wondering if someone else has experienced similar problems.

 

[litdog83z]

noone's ever had a similar problem?

 

[fontana]

What kind of timing light do you have? Is it an inductive type where you just clamp it around the ignition wire? Does it also have a little arrow on it to indicate which way to clamp it to the wires? If so, just clamp it on the wires the opposite way on the side that's messin' up. See if that works.

Wayne

 

[litdog83z]

What kind of timing light do you have? Is it an inductive type where you just clamp it around the ignition wire? Does it also have a little arrow on it to indicate which way to clamp it to the wires? If so, just clamp it on the wires the opposite way on the side that's messin' up. See if that works.

Wayne

yeah, it's the kind that clamps on.

I clamped it on both ways today and it seemed ok for a minute, then when the car got warmed up a bit and dropped the rpms some at idle it started doing it again, so it's not the timing light being hooked up wrong.

Maybe old plug wires crossing?

 

[norbs]

I have seen this on MANY buicks with type I igniton. It usually means the module is no good, but its not a good test. You need the caspers tester to be sure.

I have swtiched to the type II ignition and its rock smooth. However if you do swtich to type II make sure you use a hot wire kit for it.

 

[wbrophy]

Norbs?

What is a hot wire kit for the type II? What do you need to do to make it? and do you need to use an 86/87 type II module (green colored at the connector)?

 

[norbs]

The part numbers are on the gnttype .org site. You need the module with the first pin missing when you look inside.


basically you want to get more voltaget to pin "M" the 3rd wire in from the front when facing the the module from the drivers side. pnk/black is the color.

You cut the wire and use the harness side (12v) to trigger a relay. Then you supply a 10 gauge wire from the alternator to the relay then from out of the relay you connect a another 10 awg wire to the connector on the coil pack wire that you just cut. YOu don';t have to do this, but it will help at high boost if the car pops.

 

[wbrophy]

Thanks

 

[litdog83z]

just threw a code 42 again... it's been a couple months since that's happened, might be because i plugged in the direct scan to the ecm for some data logging though... :-/