Fuel Pressure Regulator - change it and report back.

 

NBcat:

Still question the crankcase air having anything to do with combusation air???

Off topic and not helping Sloanie, merely academic.

Even engines with huge amounts of crankcase blow by can run quite decently. Been there, more than once...

Carl

 

Thanks for the feedback guys. So, I have a fuel pressure regulator coming today. Ready to stop spending money but feel this will sell better once it is running correctly. I will hold off on pulling the distributor. I did remove the cap and rotor and try to move the shaft. Seem tight. However, I will pull it if need be in the end. More to follow....

 

So, I installed the fuel pressure regulator and it does run better. But, when you rev it up setting still it picks up RPM's fine now. No hesitation. When you go to take off or break torque it it starts bucking and shacking like the spark is breaking down. Again, I do have the distributor loose and change the timing by ear and can get it running real good or make it worse. But it will not pull load. Sloane

 

I replaced my injectors and it fixed as lot of issues, one of my fuel tanks had rusted out badly which was the initial problem and required a new fuel pump, tanks to be cleaned and a clean out of the fuel lines.

The other major issue is wiring connections and bad earths, check and clean every connector you find and doubly check all earth connections around the motor and chassis.

The air injection system on my 4.2 was also faulty, mainly a noisy air pump, so I just removed the whole system and plugged the holes in the cylinder head with 1/8th bsp grub screws, one less thing to diagnose anyway

 

Stoney85, Thanks for the feedback. I had thought of a ground issue and ran a Double 0 cable from the frame to the motor. No difference. Not liking the idear of changing the injectors..... Sloanie

 

Just for giggles.....


I know you replaced the fuel filter but pull it again and empty the contents into a clean jar. What you see, or don't see, will help decide your next steps.

Won't take but 20 minutes and costs nothing

Cheers
DD

 

I just finished pulling the distributor and checked shaft end play with a dial indicator on a mag base. I did have .006 at the very top of the shaft. Didn't seem alarming to me. I took the mag pickup out and took it down to the advance weights. Only concern I had were with the advance weights so I lube them. Seem fine now. I did clean the little copper ground tab that runs on the two piece mag pickup plate thinking this may be an issue. set the pickup gap at .008 per the book. Runs the same. The plugs are all black. I put another spark plug on a wire while it was running to see what the spark looked like and it seem to be good and blue. Filter is easy to get to. I'll check it later as I'm giving up for the evening. Thanks Sloanie

 

Hey Guys, I'm back working on the Jag. I pulled all the leads off my injectors and checked Ohm's resistance in each injector terminal back to ground and across both terminals. all injectors were the same. Now, when I check the harness connectors they are different. So, Cyl #1,2 & 3 all have the same Ohm's resistance one each terminal and both together. However, Cyl 4,5 &6 has an open on one wire on each connector. Also, when I check the Ohm's resistance between the two leads it is open. I turn the key on and do have battery voltage on one wire of each connector. I am wondering if the injector driver in the ECU is bad. I did take the connector apart on the injector harness to the body and it looks just fine with no corrosion. Comments?

Is there a OBD connector??? I cannot locate one.... Thanks Sloanie

 

Hmmmmm

I'm on my first cup of coffee. Not enough for rational mulling

When you say "open on one wire on each connector" you're referring to no continuity between the two terminals of the unplugged connector, correct? I think that's what you would want....suggesting 4-5-6 are OK but 1-2-3 are not. If I'm understanding you correctly.



Good. At least supply voltage is verified

With the connectors *plugged in* to the injectors, and back-probing with your meter, you should see battery voltage on both wires, key on, engine off



Might well be, but ECU failures seldom occur on these cars. Of course 'seldom' isn't the same as "never'.



Open up the entire harness. They are notorious for problems. The insulation becomes brittle and cracks open all over the place. There's possibility you have some bare spots touching each other inside the harness

Also, just for giggles, inspect/clean/tighten the bundle of ground wires at the rear of the water rail. The entire fuel injection system grounds here. Can't hurt.

No OBD on these cars

Cheers
DD

 

Doug, Thanks for the feedback. I pulled the ground wires off the water manifold. There were several (3-4) on one terminal end. I cleaned the terminal end, the bolt and the water manifold and reinstalled it. No change. Maybe I should cut the terminal end off and replace it? I will check for battery voltage with the injector leads connected with the key on and engine off on each wire and see what I have.

Yes, when checking resistance on the injector wires when I had them disconnected, Cyl 4,5,6 Had resistance one each wire to ground and when I checked the two leads together.

Cyl 1,2,3 had resistance on one wire only to ground. The other wire seem open or no resistance at all. There was no resistance when I check the two terminals together. This made me feel like the injector drivers or the harness had a problem.

I agree, any time I move the harness to check it I get another crack in the insulation of the wires somewhere... Sloanie