orangeIroc

I swapped a 2001 f-body ls1/t56 into my 87 camaro over the winter and am still having issues getting it running correctly. The engine was sitting in a 94 trans am not hooked up when I purchased it. The seller didn't know a whole lot about the engine, all he said was he thought it had a cam. I have installed it and got it running but the idle is high and I get an occasional p0300 random misfire code. Without knowing if it was properly tuned while it was last running or what the setup was, it's hard for me to know if the issues are tuning related or there's a issue with the engine/sensors. I have contacted a couple of tuners but both have indicated that the car needs to be running 100% for them to tune. All of the vacuum lines are new and I've checked the intake for leaks and don't see any. It has new plugs, wires, 02 sensors, maf sensor, iat sensor, and map sensor. It idles around 1500 at a stand still and almost 2500 while rolling with the clutch in. If I place a piece of tape over the small hole on the throttle blade then it idles around 1300 standstill 1700 rolling. It has decent power but seems to be lacking low end and overall seems less than it should. I am out of ideas for things to try and am tired of replacing parts every weekend with no improvement. I know the p0300 could be from the misfire tables not being adjusted for the cam but could the idle symptoms be from never being tuned for the cam?

Any help is much appreciated.

QwkTrip

iTrader: (22)

A shop that tunes but doesn't know how to build or fix is not a shop I would go to. Suggest you keep hunting for a shop that can take it 'as is' and make it run right (if you want somebody to do that for you).

kenney001

iTrader: (1)

If it were me, I would contact a company that does mail-order-tunes, give them the specs you know, and have the ECM tuned for that engine. A good mail-order tuner is cheap and can get the car running decently if it was a tune issue. If that gets the idle down correctly, then you can take it to a physical tuner.

Have you checked for a vacuum leak? If the engine can run on its own, spray some carb cleaner around the intake base, back of the manifold by the MAP sensor (there is a vacuum port there if you havent plugged it) and around the throttle body. If you get hesitation, replace seals, make sure vacuum ports are plugged, and try again. A Factory LS has 3 vacuum ports, 2 on the throttle body, and one in the back underneath the MAP. Also plug the brake booster line in case your booster is leaking.

Otherwise, get a cheap scan-tool and make sure you are reading sensors properly. Check IAT, TPS, CTS, O2 Banks 1/2. Fast idle is usually a vacuum leak or too much air post-maf issue if not a tune

cypris09

iTrader: (1)

I'd say on top of looking for leaks, check out the throttle body. Iv read mostly on ls1 tech. People either drill out that small hole to make it a little bigger or play with the throttle adjustment screw. Maybe someone did that?
I personally went with Texas speed mail order. They got it running pretty good and with a few more data logs it's close. I think you need to go to someone who will help you throughout the process not someone who tells you they can't help.

orangeIroc

Below are the numbers I can read with my obd2 gauge.

At idle: (1500 rpm)
Temp: 197 degrees f
TPS: 0%
Maf g/s: 13
Map: 52 kPa
Timing advance: 9.5 - 10 degrees
Short term fuel trim - bank 1: 1 to 3 bank 2 1 to 3 (not sure what units this is, was jumping around)
Long term fuel trim bank 1: 7. Bank 2: 11
O2 voltage: bank 1: all over the place from .04 v to 7 v
O2 voltage: bank 2: same as bank 1

After idling for about 2 minutes it threw the p0300 code. This is with the hole on the throttle blade not taped.


Does this info help at all?

86White_T/A305

If all else you replaced pretty much every sensor and the results are the same and you know a cam has been installed.Cant find any vacuum leaks..id check the injectors also for your own sake of knowing if they have or havent been changed before.

Id also suggest looking at the throttle and take it off.If the throttle blade has a hole drilled into..plus the blade is resting with a decent airgap at idle.there is an adjustment torx screw that you can lower down which will decrease your idle. This will be a good time to clean the entire throttle body also. Lower the throttle blade till its closed.From here your going to spend time starting up the car and seeing if the idle comes down or stalls and maybe slightly adjust the throttle blade a hair open.Once you can get it to barely idle without reving it..you will have to reset/learn the new throttle position and it should start and idle pretty smoothly with the iac..you might do this process 2 or 3 times for it to be happy.Clear the codes and see if it comes back after driving around some

cypris09

iTrader: (1)

I was reading on ls1tech that sone people have found broken springs. So if all else has failed you can pull the valve covers to make sure. We just had an envoy at the shop with 2 plugged cats, once we replaced that we learned that 2 different valve springs were broke so it can happen both stock and in camped stuff

orangeIroc

So I tested the iac and it was not working at all, replaced it and the idle is now lower however it now doesn't like to stay running. I reset the computer and did the idle relearn process and it helped a little but still is stalling sometimes when In neutral /clutch in. The car seems to have less power now and I am also still getting the p0300 code.

orangeIroc

I checked the compression today. I did it without warming up the engine so the numbers may be off some but cylinders 2, 4, 6, and 8 were all around 130 psi. 1, 3, 5, and 7 were all around 60. There is no signs of coolant in the oil. Oil consumption seems excessive but doesn't seem to visually smoke. Any ideas what would cause only 1 side to to have low compression? High mileage should be equally low in both sides. I would think a bad head gasket would affect 1 or 2 cylinders but not 4.