XJS V12 starting trouble....
#21
#22
#23
Hi
Just before you go Splashing the Cash
If you put a Clamp on the Fuel Return pipe coming out of the back of the FPR on 'B' Bank
(protect the Fuel Pipe from wrench jaws with a piece of rubber or rag)
Then it would artificially raise the Fuel Pressure in the Fuel Rail, so that you would be able to tell if the diaphragm in the FPR has been ruptured and needs replacing
Just before you go Splashing the Cash
If you put a Clamp on the Fuel Return pipe coming out of the back of the FPR on 'B' Bank
(protect the Fuel Pipe from wrench jaws with a piece of rubber or rag)
Then it would artificially raise the Fuel Pressure in the Fuel Rail, so that you would be able to tell if the diaphragm in the FPR has been ruptured and needs replacing
#24
The following 2 users liked this post by orangeblossom:
Grant Francis (12-31-2018),
Greg in France (12-30-2018)
#25
Thanks for the input.
Things tried today.....
Also anyone know what the pipe is supposed to be attached to? Its on the rear RHS of the motor and can't find a home for this end.....
Thanks again
Simon
Things tried today.....
- Replaced filter, I blew through the old one and there was a lot of restriction, new one much better.
- Drained surge tank and checked for debris. Got a load of petrol in the face so I guess I am now part of the club. All very clean, the petrol,not the face.
- Pulled off front 2 injectors, disconnected coils, turned over. Both injectors fired well into a clear bottle.
- Cleaned the connectors of the resistor pack with contact cleaner and a small wire brush.
- Pulled off fuel lines from FPR and I have read that if they are ok they don't leak and diaphragm inside is still intact?
- Put it all back together and still didn't run, chugged and died exactly as before.
Also anyone know what the pipe is supposed to be attached to? Its on the rear RHS of the motor and can't find a home for this end.....
Thanks again
Simon
looking at its length, and location, I’d think it could just reach the vacuum advance.
Last edited by JigJag; 12-30-2018 at 08:43 AM.
#26
#27
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Yes.
Marelli = no vacuum advance
Not much to go wrong with the distributor itself on a Marelli car. I'd put that at the bottom of the list, personally
Cheers
DD
Marelli = no vacuum advance
Cleaned the amplifiers and no difference, I will fit the new dizzy when it turns up, if no joy then amplifiers next.........
Cheers
DD
The following users liked this post:
Greg in France (12-31-2018)
#29
Buying Marelli ignition amps at great cost is *not* necessary. Look up on Ebay for Ignition Module VE520225 Cambiare 1637546 link
I've looked into these prior to buying and they are used on a number of European cars - 35,000km later and I've had no issues. I do have my original ones if someone wants a working 'previously enjoyed' set.
I've looked into these prior to buying and they are used on a number of European cars - 35,000km later and I've had no issues. I do have my original ones if someone wants a working 'previously enjoyed' set.
#30
Valve at rear of right hand side may be solenoid vacuum valve but l can't check connection positions on my car at the moment and that vacuum line may connect to spigot beneath throttle body or at rear of manifold. It is possible if that is where it should be connected maybe the ECU is not getting a manifold vacuum reading.
Has the connection etc. to air temp sensor been checked and also check the air and coolant temp sensor connectors are not transposed.
Has the connection etc. to air temp sensor been checked and also check the air and coolant temp sensor connectors are not transposed.
#31
#32
The following users liked this post:
orangeblossom (01-06-2019)
#34
If there is a spark, and it is at the right time, and fat and blue, then you have no fuel. Have you tried removing an injector and testing it into a jar while a friend turns the car on the starter? One of the front two injectors are easiest to remove.
Last edited by Greg in France; 01-06-2019 at 10:13 AM.
#36
OK
Is there any popping and banging at all when you try to start the car?
Is there any popping and banging at all when you try to start the car?
- If no, are the plugs wet? If not wet, then when cranking you do not have injection pulses.
- If wet, you do not have a good enough spark.
- If not good enough spark, use a spare HT lead from any dizzy cap plug lead post to ground, and while engine is turned over, look to verify a really strong blue spark.
Last edited by Greg in France; 01-06-2019 at 01:26 PM.
#37
#38
Update.
Replaced front crank sensor. not firing at all.I did the spare lead thing, no spark. I put the old ignition amps back on a lo and behold a strong spark. The car still coughs and splutters and dies though.......
So replaced pretty much all the ignition system and made zero difference.
I removed the 2 front fuel injectors as suggested and they both fire into the jar whilst turning over.......
Replaced front crank sensor. not firing at all.I did the spare lead thing, no spark. I put the old ignition amps back on a lo and behold a strong spark. The car still coughs and splutters and dies though.......
So replaced pretty much all the ignition system and made zero difference.
I removed the 2 front fuel injectors as suggested and they both fire into the jar whilst turning over.......
#39
If the car is popping and banging, then for whatever reason, and I do not know about the marelli cars, the ignition timing is out. You are aware the firing order goes anticlockwise round the dizzy cap? You are certain that cylinder A1 (RHS front cylinder) is sparking on its compression stroke just before TDC?
Have you renewed the rear sensor on the other end of the crank? That working is essential to make the car run.
Greg
Have you renewed the rear sensor on the other end of the crank? That working is essential to make the car run.
Greg
Last edited by Greg in France; 01-12-2019 at 02:24 PM.
#40
Hi Simon
This is what I used to Check the Firing Order of my 1990 V12 Marelli
Have a look at the link below it may help
With Thanks to Jig Jag
Firing Order XJS V12
This is what I used to Check the Firing Order of my 1990 V12 Marelli
Have a look at the link below it may help
With Thanks to Jig Jag
Firing Order XJS V12
Last edited by orangeblossom; 01-12-2019 at 05:04 PM.