Fuel issues?

[redsunbeam]

I have an engine and gearbox out of a soarer in my rover p5, It turns over but fires only briefly ( couple of seconds ) and then dies. It looks to me like a fuel problem. I put a gauge on the fuel line and found it to be running at 50psi which i believe is too high ?? I have a correct fuel pump on the way which should correct this. When the pump is stopped the pressure holds around 35psi which should mean the PRV is ok?? The other immediate possible is the injectors sticking?? The engine has been sat for a couple of years. Is there a way to check them in position. I have 12v to them, but no way of checking the pulse when running. If i put 12v to one pin and earth the other should i hear a click? Whilst having a poke around with the test meter i noticed the cylinder heads are not earthed. Do they need to be? The rest of the engine is. Any suggestions welcome.

 

[samsdad]

Refer back to wiring diagrams and go from there. You have a wiring issue probably with fuel pump control. I had the opposite problem when I did my first one.. Bloody thing wouldn't turn off yet at that time there were no wiring diagrams

 

[redsunbeam]

Wiring issue is a possibility, i have tried running with the fuel pump on permanently ( fed from ignition switch so no ecu control of pump ) and have the same problem. Will go through the rest of the wiring to recheck. Found i had missed the sensor ground on the ecu last time i checked through. I thought that was the problem, but it still persists.

 

[redsunbeam]

Its getting worse...........
Thought i would pull any fault codes from the ecu to see if that would shed any light on whats going on. I cant get any fault codes because its not switching W to earth. I have 12v at pin W. It should switch with the ignition on but engine not started? Have also tried bridging TE1 and E1 in the diagnostic socket. Have checked ecu earths, all 5 connected. Pin W is 11 ohms to earth.
Anyone any ideas?

 

[redsunbeam]

Next update, this is like playing table tennis on your own - anyone feel free to chip in
Have opened up the ECU to be greated by a capacitor relieving itself over a group of transistors.

Anyone in the uk had theirs repaired?

 

[redsunbeam]

Now have another ecu so that i can get fault codes out, getting
31 - air flow meter. That shouldnt stop it from starting?
15 - ignition 2. Whats that then??

 

[redsunbeam]

Have swapped over the ignitors and the fault stays as 15 which is number 2. So either its wiring or the coil??

 

[redsunbeam]

Anybody ? Anything?

 

[gloverman]

try swapping the coils over. They are both the same and see if the fault code changes.

 

[redsunbeam]

Swapped the coils over this morning and checked them whilst i was at it, 0.7 ohms on the primary and 11.5k on the secondary. Its made no difference. Still have code 15.
Fuel pump is fed straight from ignition and runs when ignition on, it sounds like a toilet systern filling, it doesnt sound right at all. It tries to fire on the first attempt, a little on the second and nothing after that just turns over.:banghead:

 

[redsunbeam]

I've had an inductive timing light on the plug leads that run across the front of the engine, 3,4,5 and 6 and have spark on all four so that should cover both distributors and both ignitors. That leaves only fuel. The pressure is ok, have had a gauge on the line. Is there a way to tell what the injectors are doing with the usual tools, ie eyes, ears and a test meter?

 

[gloverman]

Have you tried running the engine with engine start? With two cans and a bit of trial and error you should be able to keep it going. Are you sure you have your fuel lines plumbed correctly? Injectors do seize but normally a bit of a tap will sort that. Did you clear the codes since changing the coils around? If you are getting a code 15 I would be looking more closely at that first. Best to fix the things you know are problems rather than the things you dont know are problems.

 

[redsunbeam]

I think i have the fuel lines in the right way round, return to the tank from the prv at the front of the engine, in to the rail at the back.
I've cleared the codes but 15 keeps returning. i dont have much to go on about the 15 code, i've swapped ignitors and coils, checked the wiring from ignitor to coil and ignitor back to ecu, and i seem to be getting spark.
I dont know where else to go with this code.
I havent tried anything like engine start yet, looks like thats the job for tomorrow.

 

[samsdad]

Again recheck wiring against the diagrams and also ECU pinouts as it sounds to me that you may be missing an ignition feed into the ECU, should be a 40-40-40 and two of the plugs are paired with a bolt in the middle and one is not, the problem is likely to be in the latter and quite likely down to one wire. A point to note is that problems like this take bloody ages to find and are more often than not something small and stupid esp when wiring an EFI engine into something that never had it in the first place

 

[redsunbeam]

Again recheck wiring against the diagrams and also ECU pinouts as it sounds to me that you may be missing an ignition feed into the ECU, should be a 40-40-40 and two of the plugs are paired with a bolt in the middle and one is not, the problem is likely to be in the latter and quite likely down to one wire. A point to note is that problems like this take bloody ages to find and are more often than not something small and stupid esp when wiring an EFI engine into something that never had it in the first place

Thanks.
Have been over and over and over the wiring till i've gone wiring blind. I still cant find the problem.
One thing that puzzles me though,
The first start attempt is met with 3 or 4 seconds of running, enough to put out the charge warning light.
After that, there is no attempt to fire.
Leave it and come back after five minutes and it fires for 3 or 4 seconds again and then nothing.
Its odds on that i have a problem with the wiring, but it as if the engine is flooding after one attempt.
Any thoughts appreciated.

 

[Bushwhacker]

Are the sparkplugs wet?

 

[redsunbeam]

A little, but it took a while to get to them.

 

[redsunbeam]

Whilst i am searching for my wiring error, im trying to address the fuel system issues. I can hear the fuel rushing through the fuel rail like a toilet cistern filling. This doesnt sound right at all. Can anyone confirm that you shouldnt be able to hear the fuel flowing in the rail please.

 

[Bushwhacker]

Whilst i am searching for my wiring error, im trying to address the fuel system issues. I can hear the fuel rushing through the fuel rail like a toilet cistern filling. This doesnt sound right at all. Can anyone confirm that you shouldnt be able to hear the fuel flowing in the rail please.

It does sound how you describe if the fuel pump is wired to run continuously.

 

[redsunbeam]

It does sound how you describe if the fuel pump is wired to run continuously.

Thank you. I can stop worrying about that then

This is totally messing with my head now,
The old ECU that has no W warning light and has damage to the board from a leaking capacitor allows the engine to fire on every attempt of the key.
The engine only fires on the first turn of the key and not unless you leave it for 5 mins does the new ECU make it fire again.
Whats going on? This cant all be down to my iffy wiring? Do i have 2 iffy ECUs?