In the process of diagnosing a miss, I found a broken wire I hope someone can help me identify (see pics). #5 cylinder on bank B seems to be missing, at least at idle. Narrowed the bank down by feeling the exhaust. A definite difference from bank A to bank B. Bank A being a smooth steady exhaust flow whereas bank B is a pulsing flow. Anyway, the offending cylinder injector is receiving an input signal, verified by a noid light check. All injectors were cleaned and tested last year when I replaced all the hoses, filters, pintle caps, etc. I'm gonna check spark next, plug, wires, rotor, etc. Guess this is a request for advice on two issues. Maybe three! Anyone out there have a factory installed sunroof? Mine will work mechanically, read cordless screwdriver, but not electrically. I REALLY do not want to pull the headliner but cannot find a wiring diagram. Thanks!

 

Hi 67 Camero

That looks like the White Shielding Wire that goes to Pin 24 of the ECU in the Boot/Trunk that uses the Signal to Fire the Injectors and is Earthed from One End Only! the ECU end (Not Both Ends) and so its sounding just like this could be the problem

Its really nothing Special, its just a piece of Coax that you might find on a TV or Radio Aerial

You could even run a length of Coax around the Outside of the Car to Test the Continuity if you wanted to

White Coax Shielding Wire that Fires the Injectors goes to Pin 24 of the Ecu in the Boot/Trunk earthed at the ECU end only

 

I was concerned about the broken black wire. If it was the coax wire you speak of, the car wouldn't run at all. It is running well, just not this cylinder. Anyway, I should have named this post "The Things You Find When You Go About Replacing the Plugs". The p.o. did not perform any work personally. He paid mucho $$$ for anything done to the car. (See pic) Guess they didn't realize they were smashing the hose when tightening down the pedestal bolts. Plug looks very fouled and, from what I've read, the wrong heat range. I'm replacing the set with NGK TR5s gapped to 0.025". I also bore-scoped the cylinder and did not see anything out of the ordinary. Still see significant cross-hatch on the cylinder walls. The hose that was smashed under the pedestal runs up and behind the drivers side relay bank and into a fuel filter open on the other end to atmosphere. Hmmm, some kind of vent? I've only removed one plug so the adventure continues. Of course I realize once this work is completed and B5 is still not firing, I have an injector issue.

 

Hi Camero

In that case I can't help you but I will get back if I think of anything else

 

The hose is the distributor vent. It pulls fresh air through the distributor cap to remove any crankcase fumes and to prevent cap explosions.
The BR7EF is the correct plug for the V12.

 

A couple things I've found during my prep for plug replacement. Air injection check valve deteriorated, and its replacement found on Amazon. Wondered where that increasing exhaust leak was coming from. Throttle position sensor wire exposed at the housing. Anyone have experience with the "brush on" wire insulation? Correct plugs on the way, BR7EFS. I don't want to say where I read that the others were correct but there is a bunch of incorrect information out there. Going to replace the hose related to and near the check valve as the exhaust leak kinda cooked everything around it.

 

Replace that TPS!
Also, if you are allowed to in your jurisdiction, remove the entire air injection disaster and plug the holes in the manifold.

 

Ok.....where is the best place to purchase a new/good TPS? I would love to remove the air injection system. Have you done this and is there a good write-up, video?

 

Re: removing the the air injection system / smog pump. Here is the guide I used: https://foreverjaguar.com/f/smog-blogdelete

Removing the air rails can be done with the engine in the car, just requires some careful cutting and maneuvering of the pipe out of there.

 

Concerning the individual injection ports in the intake manifold, why not just tap them to accept a small pipe plug? I think I'm gonna go forward with this and also remove the A/C compressor as it doesn't work anyway.

 

The usual specialist suppliers.

All you need to do is to remove the stuff on the top of the engine (the long distribution pipe each side and the small ones going down to the manifold) and plug the holes by tapping them (it is only ally) and screwing in a grub screw. The pipe you cannot get at along the side of the engine just leave in position.

 

I am going to do all that plus remove the a/c compressor, associated lines and the cruise control bellows as these things do not work currently. I will be able to remove the air injection pump also. I'll keep all this stuff in the event I want to attempt to get it working in the future...but probably not. AND! I realize after doing all this, I may continue to have an injector issue. Once again, thank you all for the time you spend answering/commenting on my issues. This site has been such a big help to me.

 

Just a note: If you remove the air compressor itself (as opposed to just deplumbing it) you need to replace it with the UK car's jockey wheel assembly, or make your own alternative arrangements for belt tightening etc.

 

Looking at the belt arrangement on my car, if I remove the a/c compressor and the air pump, I will not have to add an idler. The power steering, water pump and alternator are driven by two belts separate from the compressor and air pump.

 

Ah, yes. I forgot you are doing without the aircon.

 

I've removed the compressor, throttle pedestal, cruise control bellows and distributor cap. I'm assuming one of the hoses coming off of the distributor base is the vent line and the other goes to the vacuum advance? Am I correct? Found the labeled "B" coil lead going to the "A" side of the distributor and vice versa. Hmmm. Also found a nasty coil lead, really corroded. Gonna get a new wire set, distributor cap and rotor.

 

Hi 67 Camaro

Lower Coil RED for 'A' Bank

Upper Coil YELLOW for 'B' Bank

If you've got these Wires from these the wrong way round then She won't Start

Alex

 

There is no vacuum advance on a Marelli car. One hose goes to a vacuum source and the other to vent/filter for fresh air.

 

Well, the car ran pretty well so I guess just the coil wires got switched. I'm getting a new set and they will be marked accordingly. Thank you so much for your reply.

 

Thank you! I thought I might be losing my mind.