Even so most of your spark components are new, that doesn`t mean there good, test the spark and find out. Heres my plan of action, let me know if it sounds logical: checking chain with valve covers off is ezier than replacing, take dist cap off turn crank clockwise by hand till timing pointer reaches a little past tdc say 5-6 deg then while watching dist rotor turn it backwards just till the dist starts to move, then see how many deg the crank moved, that will tell you how much slack it has, 7-8 deg is about the limit getting pretty worn at this point any less its probably not the problem, if you suspect its jumped then with the valve covers off look at either #1 or #6 cyl rocker arms does not matter which but both pistons come to the top at same time, then while turning engine over ( by hand or crank bolt either way you can) till the exhaust rocker arm is just closing and the intake is just opening about the same amount, you can move the crank back and forth if you have to unless theres way to much slack, just get them about even then look at the crank timing pointer it should be somewhere around 0 deg or tdc anything around 15+ deg either way and you have a problem.one tooth off is 15 deg. I couldn't be sure if it was coming from the front main seal or from the front of the oil pan. Based on the 6.0-litre LS2 engine which featured in HSV’s models, the 6.0-litre L98 replaced the 5.7-litre LS1. The following year, Chevy introduced the L98, a genuinely modern fuel-injected engine that looked the part. What issues/problems have you had with your 10-15 Camaro SS A6 automatic? A vacuum leak in any of the hoses can be the culprit—inspect them all for leaks. any way hope i could help any good luck Mikey. After going over (roughly) 60% throttle while accelerating the engine revs … If you havent replaced the oxegyn sensors it would proboly be a good idea to do so, imo, as far as a mass air sensor, see if someone will let you try their's long enough to see if it helps..I know it should show you codes but sometimes you never know, 1 more thing I would check is to be sure your cat converters are'nt stopped up... And actually.. could this be a problem with the injectors being cloged or dirty? ARG At this point Im considering pulling the whole TPI off and sticking a damn carb on it. Fuel Rail Pressurization: When you first turn the key to the “on” position, the fuelpump will run for 2 … The worst complaints are engine, fuel system, and cooling system problems. but, your problem is fuel or spark timing or valve timing related. TPS TPS TPS!!!!! Power increased to 270 kW (362 bhp) at 5700 rpm and 530 N⋅m (391 lb⋅ft) at 4400 rpm. While driving at any speed let up on gas pedal and then excellerate, it buckles or backlashes. In 1985, the L98 5.7-liter, small-block V-8 displaced 350 cubic-inches and had an overhead valve configuration with cast-iron blocks. When the valve is unseated, the engine should run rough, and the further you push the valve’s diaphragm inward rougher running and/or stalling may occur. The engine had a bore and stroke of 4.0 x 3.48 inches with a compression ratio of 9.0:1. not trying to be redundant here just trying to help get you on track, many times i myself have dwelled on a problem in wrong area only to find out i had missed something because i assumed it was good when it was not. The engine was the old Blue Flame six with mechanical lifters and a compression ratio boost to 8.0:1 to produce a modest 150 hp. However, we recommended leaving them as thick as possible when running boost. Since Holden did not use the displacement on demand technology of the L76, some redundant hardware was removed to form the L98. I really like the 10-15 Camaro SS but I don't like the AFM. The last time they still could not find the problem, just costing me a load of $. Ive been battling the problem for 2 years now and havent been able to figure out whats going on, fortunatly its not my daily driver . I did not do this and had no problems with clearance. The L98 engine was the standard engine option on Chevrolet (or Chevy) Corvettes produced from 1985 to 1991. L98 Timing Chain Replacement. scanner), tps and such while car is sitting for proper voltages, mass air flow usually has to be driven or loaded for true readings (look for wacky flow numbers) also try tapping lightly on af sensor if makes difference sensor at fault , as far as injectors go, look for high or low ms times low ms times indicate to much fuel high ms times starving for fuel usually cloged injectors will show high ms times even at idle, even fuel pressures being off will throw the readings off so you will have to baseline oem specs with fuel pressure in order to get correct oem readings, also i noticed you said open loop status, an ecm starts in open loop status when you start the car and when everything is ready it closes the loop creating a chain if you will, if theres a problem it will stay in open loop, if it closes the loop then its doing its job, some models will close the loop then open it after the car sits idleing for a while this is ok is sending it rich to cool things down in some models but should resume loop as soon as accellerated, also some models have map sensors which also help control timing and fuel curves as well, and they are vacume controlled as well and good for pluged or broken vacume lines, and all this is assuming the engine has no mechanical vaults creating false vacume readings such as big cams, valves not sealing, bad cam lobes, weak valve springs, incorect cam timing etc. Hour and typically results in a car engine, which enhances the combustion process that occurs in each cylinder... 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