Conversions & Swaps LSX Engines in Non-LSX Vehicles
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Old Aug 24, 2010 | 10:10 PM
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OK got the camaro running. it would rev good the other day. havent driven it anywhere. now it will crank but idles low bout 750 rpms, wont rev if you hit the accelerator but you can slowly ease into the throttle and it will increase rpms but it will be rough sounding.

inj pulse at both banks at 1200 rpms is about 6.2mV

MAP kPa 91
map V 4.27
Baro kPA 91
tps at 0% throttle is 0.51V and at 100% is about 4.20V

fuel psi is constant at 58psi

car is speed density. rear O2s deleted, MAF deleted. IAC tuned out.

Any ideas? We have Charlotte Auto Fair in two days for the show and gotta figure this out.
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Old Aug 24, 2010 | 11:41 PM
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update...motor stopped running all together. wont start, just spins over. throw a shot of brake cleaner in and it fires right up.. any ideas why the injectors arent pulsing before it is running?
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Old Aug 25, 2010 | 01:29 AM
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Make sure you have good solid grounds and all the grounds are connected. Make sure the engine and transmission are grounded well (i.e. NOT through the engine / trans mounts) Did you build your own harness or did you buy one? Don't take offense to this but if you built your own harness, that is the next place I would look.

I had a battery terminal issue which gave me fits until I found it. Ironically the new terminals from the previous owner weren't setup well. Even though the cables and terminals were new they still had conductivity issues because the install was a bit of a hack job and the new engine drew more current.
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Old Aug 25, 2010 | 09:11 AM
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I did the harness. I've checked the hots and grounds at the pcm in key on and start and thy are hot. The orange wire to the pcm is hot all times. Got power and ground tocam sensor, got 5V to tps and ground. Got power to injectors. Just they don't pulse until the car is running. When you crank it off brake cleaner it runs fine and can drive down the road.
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Old Aug 25, 2010 | 11:49 AM
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Are the injectors themselves good? How about the rails? You could have good psi, but gummed up rails.

Also for the hell of it throw some extra grounding wires on. Can't hurt.
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Old Aug 25, 2010 | 12:30 PM
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Injectors are good. Motor was running fine the other day. Has fairly new injectors and new edelbrock rails. It runs good when you get it started. Just don't know why the injectors don't pulse in start but they do in run.
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Old Aug 25, 2010 | 06:31 PM
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you mentioned a map kpa of 91. Is that at Idle? should be 30-40 I would think at idle.

Recheck TPS, could be entering clearflood somehow preventing injectors from firing at crank speeds.????

is PCM programmed correctly for the injectors? flex fuel programming with normal injectors?
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Old Aug 25, 2010 | 07:56 PM
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Originally Posted by busta9876
you mentioned a map kpa of 91. Is that at Idle? should be 30-40 I would think at idle.

Recheck TPS, could be entering clearflood somehow preventing injectors from firing at crank speeds.????

is PCM programmed correctly for the injectors? flex fuel programming with normal injectors?


the kPa is at about 1200 rpms. idle is around 1150. cam is a custom grind 24x,25x

pcm was programed for this motor in the car it came out of. if the computer sat with no battery to it for, say 4 months, could it have lost its tune in the pcm? ok update..... now i went outside and put a new cam and crank sensor in it. motor spins over and hits one time and cuts off. not getting an injector pulse while in run now. but injectors have power key on... VATS is disabled btw,
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Old Aug 26, 2010 | 08:52 AM
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ok motor is running now but has a hesitation off idle and is backfiring through the exhaust on decel sometimes but not throwing a code.. checked sensors and grounds and everything looks good. could there be something that when it was tuned on the other car which had a stalled th350 and ive got an m6. maybe needs a retune?
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Old Aug 26, 2010 | 11:58 AM
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Originally Posted by NSTIGATR
ok motor is running now but has a hesitation off idle and is backfiring through the exhaust on decel sometimes but not throwing a code.. checked sensors and grounds and everything looks good. could there be something that when it was tuned on the other car which had a stalled th350 and ive got an m6. maybe needs a retune?
regardless definitely get a retune for the m6.
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