Scott Mauller

I washed my engine bay covering above the waterpump and alternator. Afterwards I tried to start it the next morning and it had a rough idle. Cleaned the MAF and all other connections surrounding the TB and same thing. Car backfires on start up and continues to have a rough idle. One thing is when I give it gas it goes away and comes back at idle and low rpm. I know most will say opti which I have looked up symptoms, but I want to try the smaller things first.

Scott Mauller

Checked again still same but I did notice if I put in reverse it has a rougher idle/miss. Unhooked MAF wouldn't start. When running I unhooked the MAF and it died.<br/>

moparman

Probably got the opti wet. May have ruined it. It's a no no to spray water around the front of the engine.

Injuneer

You need to add a "Signature" with basic info about your car. The only clue was the inclusion of the word "opti". Even having figured out that you have an LT1, you need to provide the year because there are subtle differences from year to year.

Include year, model, trans and any major mods so we can provide you with the most accurate help.

Scott Mauller

1994 z28 A4

Scott Mauller

Haha sorry about that

94 z28 A4 - High flow cat/Y, Flowmaster, Moroso CAI, 1le elbow, MSD wires, line lock, BMR adj tq arm/LCA's/panhard bar, Vigilante 3300 stall and shift kit.

Injuneer

You don't need to type a "Signature" for every post. You set up a Signature in your profile, and it is automatically appended to every post. See the short line above "Fred" in my post. That's where the Signature starts. Everything below that is from my profile.

Go here for instructions:

https://www.camaroz28.com/forums/lt1...nature-879835/

Injuneer

The 94 Opti is "unvented" (95-97 is "vented") and is more susceptible to moisture problems. But before you assume it's the Opti causing the problems, check all the plug wires and the coil wire for corrosion at the terminal ends - in the Opti and in the coil. Check the wires for damaged insulation, cracks, etc. That's where the moisture will attack the ignition, and cause misfires and cross-firing. Look for a buildup of crud on the coil or Opti. That attracts/holds moisture, and offers a low resistance path for the spark to wander around.

Scott Mauller

I'm gonna check the IAC when I get home. I did notice the coil had corrosion and I spray cleaner and some wire dryer on it gonna get some grease tonight. The could wire does not seem to click i noticed. MSD wires looks like 8.5mm

94 z28 A4 - High flow cat/Y, Flowmaster, Moroso CAI, 1le elbow, MSD wires, line lock, BMR adj tq arm/LCA's/panhard bar,SLP weld in sfc's, Bilstien hd's, Vigilante 3300 stall and shift kit.

Scott Mauller

Fixed!!! Cleaned my IAC and after a few starts car was back to normal. IAC was not only full of carbon (126k) but looked like some degreaser/grease was inside. Glad it wasn't my opti!

94 z28 A4 - High flow cat/Y, Flowmaster, Moroso CAI, 1le elbow, MSD wires, line lock, BMR adj tq arm/LCA's/panhard bar,SLP weld in sfc's, Bilstien hd's, Vigilante 3300 stall and shift kit.