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Compression check might help. Cranking compression on a cam advanced a tooth will be absurdly high unless you have PTV.
Cam retarded a tooth will have low cranking compression.
Bent valves, no compression.
You can also try to degree the cam without pulling any major hardware. Use the valve lift to find your cam events. Compare to cam card. If everything is on point you would then know you just need a tune. If the events are way off, then you know you need to correct the timing chain.
I pulled the timing cover and it does not appear to be off a tooth:
I did not pull the oil pan thus I didn't pull the oil pump. You'll have to take my word that the tooth sticking straight up has a dot on it.
Does this look correct? I am hoping that a cam off a tooth would be fairly obvious.
If the cam chain is correct, what else would cause misfiring?
The spark plugs, wires, and coils are relatively new(2 years) and under 1k miles. I pulled a spark plug and verified gap(0.040") and condition. The plugs are NGK 7397 TR5IX Iridium.
The fuel pump is putting out plenty of pressure and I've verified at the fuel rail... pump is stock 99 Camaro unit.
Would failing fuel injectors cause this issue? They are original(2004) with about 65k miles on them.
Engine got about 20-30k miles of running before the cam swap. Total miles on the engine is about 60k. I was delayed in doing a post cam fire up for an extended time
Originally Posted by madmann26
What happened leading up to the running rough?
Each time that’s happened to me I’ve had a broken ring land, or 2. Lol
Compression test it at least.
Nothing really happened before lead up. I took a running completely stock engine, downed it for a cam and valve spring swap, and after extended delay of firing it up, it runs like hell.
From my picture, would you agree that the timing chain was installed properly based upon the marks? If I was off a tooth, it should be very obvious to tell?
this swap had all the same sensor locations? Meaning, Same Crank sensor locations, knock sensors etc?? I once switched my LS1 to an LS2 and purchased the Cam/Knock sensor extension harness and the harness had two swapped wires in it.
In fact, a lot of people purchased this same harness and had the same problem.
Confirm that the PCM's getting the CAM and Crank sensor signal or it will run like total ****.
Lastly,
you did a cam swap and when you fired it up, it ran like ****? Are all the Pushrods set correctly? Just brainstorming with you.
this swap had all the same sensor locations? Meaning, Same Crank sensor locations, knock sensors etc?? I once switched my LS1 to an LS2 and purchased the Cam/Knock sensor extension harness and the harness had two swapped wires in it.
In fact, a lot of people purchased this same harness and had the same problem.
Confirm that the PCM's getting the CAM and Crank sensor signal or it will run like total ****.
Lastly,
you did a cam swap and when you fired it up, it ran like ****? Are all the Pushrods set correctly? Just brainstorming with you.
Thank you for taking the time to brain storm.
From a sensor standpoint, everything is stock and in stock location except for MAF sensor(2004 Silverado 2500HD 6.0L). It is about 1 foot away from the throttle body after a 90 degree. This is a massaged stock harness.
Correct, after swapping the cam and firing it up, it ran like ****.
I'm unsure what you mean by "pushrods set correctly". Would you clarify that?
I think he means the preload on the lifters, but with that cam your stock pushrods should be fine.
If you could put the previous tune in that should eliminate a tuning issue, in fact that cam should still run fairly well on the stock tune.
Lots of threads here where guys do a cam swap and coil harnesses end up getting swapped L to R or other electrical gremlins cause the engine to run terrible. I’ve seen a single side coil harness fuse blow and the engine run like a turd. I’d triple check all of my harness and grounds as well as my fuel pressure before I went further. 99% of the time it’s something ridiculously simple.
I ordered some replacement fuel injectors and pulled the old ones out.
From watching videos after the fact, it appears there is nothing special about replacing injectors. But in my case, they all leak like a MFer. I bought these: https://www.ebay.com/itm/8-x-Genuine...72.m2749.l2649
They are listed as Delphi part number 25343789. Which are supposed to replace Delphi part numbers 25317628, 25320288.
So while I sit and scratch my head, I checked the old injectors. Only three out of eight were working So the problem I ran into is bad injectors. The bad is I can't get the new injectors to seal up.
Is it worth sending my injectors in to get rebuild/flow matched/etc? If so, is there a good spot to send them to?
*follow up #2*
It looks like I'm fighting a p0200 code and am at a loss.
I have checked that the injectors have +12v. The injectors are brand new. One wiring difference from stock is I combined the INJ1 and INJ2 circuits into one fuse. So these means the coils and injectors are on one 30 amp circuit.
I checked the wires from PCM to injector on both a stock un-molested harness and this modified harness. The pinout is correct AND they all read 0.3 ohms.
I checked all the grounds for the pcm (Blue 1, 24, 27,40, 64 and 67/Green 1 and 40) They also read 0.3 ohms each. I also confirmed the ground point against the battery for continuity. The slight difference from a stock harness is I have all the grounds tied together(IAT/MAF, TAC, Coils).
I am waiting for a noid light but I'm sure it is going to tell me something is hosed.
It ran fine and then you somehow lost 5 injectors during the cam swap? SEVERELY unlikely, basically impossible
(lost = they went bad)
Did ANYTHING else change besides the cam?
ALWAYS with diagnostic keep focus on what changed when you have a good running condition to a bad running condition after doing repairs or replacement of parts
Cam sensor or crank sensor? If so put old one back in
Look at any and all things that changed or were moved.
Run compression test before you do anything else
I'm willing to bet your old injectors are just fine. You can use a stethoscope to listen for injector function by the way. Good ones make a sharp clack sound. Dead ones you'll hear a thud do to noise transfer from the other injectors
Did you possibly accidentally swap the coil packs from one side to the other?
Unplug any coils and remove the coil wiring from the packs? (seen this cause hell when the coils get plugged in wrong and fire the wrong cylinder)
Pull up the wire diagrams and make sure all the coils are connected to the proper cylinders
01-28-2020, 10:59 AM
What are symptoms of cam chain being off(LQ4)? 
So the problem I ran into is bad injectors. The bad is I can't get the new injectors to seal up.