jcorkin

I recently bought a 1999 camaro z28 for a very reasonable price. The car has had some work done to it and has some issues. Ill start with what I know about the car. It has an SLP lid, long tube headers that run into straight pipes that have turn downs right at the rear axle with no mufflers or cats(sounds very aggressive and doesnt drone going down the road), ram air hood, nice drilled and slotted rotors, c6 corvette wheels, has larger sway bars with full chassis stiffening and aluminum coilovers all around. I know the intake has been off the car as the valley cover and intake bolts are now all polished allen head bolts.

The camaro runs very strong and im pretty certain the rear gear has been changed as the car has a 6 speed and ive done 126mph in 3rd gear on gps, guessing thats not stock gearing.

Now for the issues. I get a check engine light for multiple things but only one really means anything. The air pump has been removed so I get a code for that and some associated codes too. I also get a code for the map sensor and have tested the wiring and everything and Im fairly certain its bad, the issue im having with the car is that i have weird idle issues. When first started it up it idles up to 2500 rpms for a couple of seconds then slowly decends to normal. When coming to a stop i push in the clutch and it revs to 2500 as long as i am coasting and then idles down after im stopped for a couple of seconds. After disconnecting and testing the map sensor wiring and clearing the code the car seemed to idle perfect. After driving it about 15 minutes the issue returned. Just wondering if the map sensor could be the culprit with my idle issue or if I need to be looking for something else. Any help is appreciated.

Also my trans needs to be rebuilt and my clutch pedal sticks down at times, ive read plenty on that issue and plan on rebuilding the clutch system and trans this winter.

Sorry for the long post but i wanted to be as detailed about my situation as i could

Fry_

Shiny allen head bolts makes me think the car ounce had a Fast intake manifold, don't know if that helps anything just a though. The rear gears probably are stock to that rear end, but that rear end probably isn't stock to that car. To go 126 in 3rd you'd need 2.73 gears, the most undesirable stock ratio offered making it the cheapest used replacement you can buy. After getting the car running right 4.10 gears for that diff or in a new 9 inch diff depending on the cars intended use should be at the top of your to do list.

garygnu

you mite have a gasket leak .you mite need a new gasket for the MAP sensor at the back of the intake .

Mercier

iTrader: (15)

Agree with Fry. Sounds like you have a good chassis and base overall to start with though.

Any idle issues, always check for vacuum leaks and clean the MAF with electronics or MAF cleaner, and then clean the throttle body and IAC with throttle body cleaner. Clear your codes, and then try it again. You might pull the MAP sensor and squirt it with some TB cleaner as well. Mine was all gunked up with PCV debris that it was not working. But I will probably buy a new one anyway. Get yourself a catch can if the previous owner took it off with the intake. It will keep all that crap out of your intake tract.

jcorkin

I actually kinda like the rear end gear the way it is, it pulls really hard in all gears yet i can hit 6th and do 65mph at 1100rpms. Ive tried pulling the map sensor but that clip is a real pain to get off of the map sensor without being able to see it. I know all of the A.I.R. system has been removed so i guess it is possible to have a leak from it somewhere. Here are some pics

Firebrian

1100 rpm at 65 mph in 6th gear is probably ok when going down a hill or a long dead flat straightaway in the mid-west. But, in all other circumstances the engine would likely be seriously underloaded/lugging. 6th isn't very useful with 2.73 gearing until you hit about 85-90 mph. I have the 3.42's and even that's difficult to keep the engine at rpm in 6th as you hit the hills on the highway. Anything under 65-70 mph and 6th is a drag.

jcorkin

Im in the midwest with nothing but flat land, so thats fine with me. I mostly use 5th and the engine makes plenty of power to get the car moving in 5th at 60mph. I may end up changing out the gears at a later time but for now not a big deal to me.

Fry_

I'd rather have 4.10s you'll still only be turning 1740rpm at 65.
This gear ratio calculator really helps with seeing the affects of gear and tire changes.
Hell you could run 4.56 gears and still be under 2k at 65. Gotta love a 0.50 overdrive, makes stupid gears streetable.

jcorkin

Forgot to post pics of my other sports car

Mercier

iTrader: (15)

Liking the old-school Vette. Get some gears dude. It will be worth it in the grin department.

jcorkin

its a 1990 z51 with a 6 speed. Highly optioned with a good amount of performance work done to it. I will probably go for gears sometime down the road but for now I gotta get the trans rebuilt as the synchros are shot in all gears including reverse and then the clutch issues to boot.