missing oil, missing power & exhaust note changed... help
missing oil, missing power & exhaust note changed... help I've been driven nuts for 2 weeks now.
The gist: stage one ls6 heads and full MS4 cam/valvetrain kit, all bolt-ons
Problems:
*2 quarts of oil missing every 700miles. no oil or smoke out exhaust no leaks ANYWHERE on the car, ultra clean. Took valve covers off no burnt oil still looks brand new.
*Missing a bucket worth of power but no bucking or backfiring idles fine, throttle still responsive. No engine codes. Compression test was:210/205/210/205/215/215/218/218, plugs clean and dry. all springs look great and all rocker arms moving as they should.
*Exhaust note changed considerably, sounds like it's under water and garbled now, no V-8 rumble. This is the major hint to me that somethings off
At this point am wondering if the tune by LMR messed up some how, happened after a drive in 103 degree weather, didn't overheat though. I'm going to check and make sure all the coils are working tomorrow. Then maybe check the fuel pressure, (maybe the fuel pump is dying slowly?) strange as that might be.
Other then that I can only think of the tune messing with the timing honorably, any other suggestions?
Thanks, JR
The gist: stage one ls6 heads and full MS4 cam/valvetrain kit, all bolt-ons
Problems:
*2 quarts of oil missing every 700miles. no oil or smoke out exhaust no leaks ANYWHERE on the car, ultra clean. Took valve covers off no burnt oil still looks brand new.
*Missing a bucket worth of power but no bucking or backfiring idles fine, throttle still responsive. No engine codes. Compression test was:210/205/210/205/215/215/218/218, plugs clean and dry. all springs look great and all rocker arms moving as they should.
*Exhaust note changed considerably, sounds like it's under water and garbled now, no V-8 rumble. This is the major hint to me that somethings off
At this point am wondering if the tune by LMR messed up some how, happened after a drive in 103 degree weather, didn't overheat though. I'm going to check and make sure all the coils are working tomorrow. Then maybe check the fuel pressure, (maybe the fuel pump is dying slowly?) strange as that might be.
Other then that I can only think of the tune messing with the timing honorably, any other suggestions?
Thanks, JR
How i fixed it/my problems.
I had a Racitronics fuel pump and hot wire kit, so i put it in. pressure was still off so I replaced the stock fuel pressure regulator with a new one, it was busted. If pressure is the problem, you will have to buy a regulator for a chevy suburban same year. or basically any Chevy suv same year with a 4.7-5.7 v-8, they all run off the same pressure. Because no parts store shows we have a regulator.
I also didn't mention i had a tapping noise also. It was a lifter. I got annoyed with all the problems so I just gave in and torn the heads off, rebuilt the motor. Got LS7 lifters and LS2 value guides, had the heads valve seals replaced(they were pretty worn), all new bolts, ect. ect. and put it all back together. PVC vavle was also stuck open so that was another problem.
All in all everything was fixed, She runs like a demon again no problems for months now and exhaust note went back the normal. Hope this helps.
Still burning though oil but at a lot slower rate, its just the way i drive (like i just stole it off the lot) look it up might be your problem too. Most LS1 I know burn some amount of oil.
I had a Racitronics fuel pump and hot wire kit, so i put it in. pressure was still off so I replaced the stock fuel pressure regulator with a new one, it was busted. If pressure is the problem, you will have to buy a regulator for a chevy suburban same year. or basically any Chevy suv same year with a 4.7-5.7 v-8, they all run off the same pressure. Because no parts store shows we have a regulator.
I also didn't mention i had a tapping noise also. It was a lifter. I got annoyed with all the problems so I just gave in and torn the heads off, rebuilt the motor. Got LS7 lifters and LS2 value guides, had the heads valve seals replaced(they were pretty worn), all new bolts, ect. ect. and put it all back together. PVC vavle was also stuck open so that was another problem.
All in all everything was fixed, She runs like a demon again no problems for months now and exhaust note went back the normal. Hope this helps.
Still burning though oil but at a lot slower rate, its just the way i drive (like i just stole it off the lot) look it up might be your problem too. Most LS1 I know burn some amount of oil.
How i fixed it/my problems.
I had a Racitronics fuel pump and hot wire kit, so i put it in. pressure was still off so I replaced the stock fuel pressure regulator with a new one, it was busted. If pressure is the problem, you will have to buy a regulator for a chevy suburban same year. or basically any Chevy suv same year with a 4.7-5.7 v-8, they all run off the same pressure. Because no parts store shows we have a regulator.
I also didn't mention i had a tapping noise also. It was a lifter. I got annoyed with all the problems so I just gave in and torn the heads off, rebuilt the motor. Got LS7 lifters and LS2 value guides, had the heads valve seals replaced(they were pretty worn), all new bolts, ect. ect. and put it all back together. PVC vavle was also stuck open so that was another problem.
All in all everything was fixed, She runs like a demon again no problems for months now and exhaust note went back the normal. Hope this helps.
Still burning though oil but at a lot slower rate, its just the way i drive (like i just stole it off the lot) look it up might be your problem too. Most LS1 I know burn some amount of oil.
I had a Racitronics fuel pump and hot wire kit, so i put it in. pressure was still off so I replaced the stock fuel pressure regulator with a new one, it was busted. If pressure is the problem, you will have to buy a regulator for a chevy suburban same year. or basically any Chevy suv same year with a 4.7-5.7 v-8, they all run off the same pressure. Because no parts store shows we have a regulator.
I also didn't mention i had a tapping noise also. It was a lifter. I got annoyed with all the problems so I just gave in and torn the heads off, rebuilt the motor. Got LS7 lifters and LS2 value guides, had the heads valve seals replaced(they were pretty worn), all new bolts, ect. ect. and put it all back together. PVC vavle was also stuck open so that was another problem.
All in all everything was fixed, She runs like a demon again no problems for months now and exhaust note went back the normal. Hope this helps.
Still burning though oil but at a lot slower rate, its just the way i drive (like i just stole it off the lot) look it up might be your problem too. Most LS1 I know burn some amount of oil.
I dont haVe any ticking noises,just the exhaust note and bucking.Also i have a stock fuel pump,so maybe its going bad along with the regulator.
