Despair!!!!!! (Electrics)

[bhpjon]

Once again the car is out of hibernation, and before i start this year i would like to sort out a major B@#;ache in the shape of my electrics.When i first got the car, i had to fit a hotstart mod as it used to refuse to start when hot, problem sorted!
Last year i had a new alarm fitted to the car (when problems started) But when i called the alarm gentleman round to see/fix the car, after having refused to start for a week, of course it fired first time and quite reasonably he said with no fault i cannot fix it. Anyway i started back into the familiar pattern of 'go for drive, stop engine, try to start 5 mins later and no fuel pump priming sound, but then after half an hour bingo once again. After calls to scrap it (which i defended on the grounds of it having little scrap value cos it's fibreglass) from my good lady ( as on the only long journey we did together last year, we sat for rather longer than is wholly pleasant, in Hartshead services on the M62 as after a loo-stop and it would not restart!. We were then taken to manchester by a recovery truck, got to destination and promptly drove it off the truck!!!
After subduing the missus, i took car to local ecu fault finder who found no fault and not a sausage in the storage memory of faults. Then relieved me of some cash.
I then took the car to an auto spark, who had the car for a whole day, who after stop starting it all day, couldn't get it to replicate the fault at all. Kindly didn't relieve me of any cash.
The other day i undid the Carcoon and pulled out the dead battery (i've lost the little adapter to croc clip to the battery) With this i took the opportunity to look at the loom 'down there'and found the fused connection to the alarm (i think) which i checked and all seemed well. Last time i posted, re-this subject, a reply came through regarding a fuse for the ECU but i can't seem to see one. I am assuming that any fuel pump fault would have been logged in the Ecu so i am back to the ECU fault or a bad earth somewhere
!!!!!!!!!!!I have even contemplated taking it to TVR!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!PLEASE HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Edited by bhpjon on Friday 2nd March 12:57

[spend]

Unless you are completely stuck on keeping the car original ~ why dont you just consider fitting a modern alarm/immobilizer ~ they will also probably have a more efficient door looking circuit.

I do note that there are 2 camps here ~ I've only ever had a 3rd party alarm & no problems, but have read with interest many faults with the standard systems.

Dave

[pupp]

One of the three 'cuts' on the immobiliser sounds like it's gone intermittent. Often, it's the starter loop due to the (un-relay assisted) loads switched through it (hence the hot-start mod's effectiveness) but the others fail too. Been there, got the tee-shirt, bypassed the circuit

[K4TRV]

Have you looked at the connections to the fuel pump ?? Not easy to get at, but subject to a lot of water spray/grime etc.

Wouldn't get too involved in the ECU and logging of problems - It's not of the modern ilke which learn and store a lot of info - it does do some but certainly nothing that will help you find a bad connection to the fuel pump for instance !!

Do suggest you check area around battery and fuses and relays - only takes a relay to be knocked sideways and cause intermittent operation.

Trev McM

[bhpjon]

spend said:

Unless you are completely stuck on keeping the car original ~ why dont you just consider fitting a modern alarm/immobilizer ~ they will also probably have a more efficient door looking circuit.

I do note that there are 2 camps here ~ I've only ever had a 3rd party alarm & no problems, but have read with interest many faults with the standard systems.

Dave

Hi Dave, thanks for that,i had a new alarm fitted which was when the issues started. cheers Jonathan

[bhpjon]

pupp said:

One of the three 'cuts' on the immobiliser sounds like it's gone intermittent. Often, it's the starter loop due to the (un-relay assisted) loads switched through it (hence the hot-start mod's effectiveness) but the others fail too. Been there, got the tee-shirt, bypassed the circuit

This seems a new avenue to explore, how do i identify this starter loop, and how would i bypass it please? thanks very much Jonathan

[bhpjon]

K4TRV said:

Have you looked at the connections to the fuel pump ?? Not easy to get at, but subject to a lot of water spray/grime etc.

Wouldn't get too involved in the ECU and logging of problems - It's not of the modern ilke which learn and store a lot of info - it does do some but certainly nothing that will help you find a bad connection to the fuel pump for instance !!

Do suggest you check area around battery and fuses and relays - only takes a relay to be knocked sideways and cause intermittent operation.

Trev McM

Cor, i wasn't expecting so many interesting replies so quickly (Does no-body work any more) I will go down this route as well ( cleaning contacts etc); interesting about the ECU ; only reason i hadn't cleaned fuel pump already was fact that it only started when new alarm was fitted and i wasn't sure if fuel pump would be heat sensitive,Thanks for these pointers, much appreciated Jonathan

[spend]

bhpjon said:

...i had a new alarm fitted which was when the issues started.

Sounds a little coincidental?..... (but in fairness I am terribly sceptical about "auto-electricians" - the quality of work does seem to vary greatly )

Dave

Just to Clarify ~ he is getting no fuel pump buzz & no starter ~ the only common link AFIK is the alarm immobilizer. Failed fuel pump / relay would not stop the car turning over ~ just as hot start would not affect fuel priming (unless the DB hot start kit has been installled very incorrectly ~ which is highly unlikely).

Edited by spend on Friday 2nd March 15:45

[TVR Thomo]

Had a similar problem which ended up being the fuel pump relay!

See topic: www.pistonheads.co.uk/gassing/topic.asp?h=0&f=8&t=308810

In the end I replaced the two relays which are tucked up behind the glove box pocket and there's been no problems since!

Hope it that easy !

Cheers
Neil.

Edited by TVR Thomo on Friday 2nd March 15:33

[Paulathome]

Jonathan,
When you say the car will not start, do you mean the engine turns over and refuses to start or the engine does not turn over?
If the engine refuses to turn over then you may have an immobiliser fault as on most TVR's the starter motor circuit is broken when the alarm is armed.
If the engine turns over but you hear no fuel pump then the fuel pump relay may be faulty or the circuit that switches the relay. May be worth changing the relays in the foot well (The two loose ones in the loom by the battery) only cost about a tenner each.
Check under the car (off side near the rear wheel) that the connections are Ok at the pump including the earth.
Also in the drivers side behind the seat, pull back the side panel and check the connectors in there as this is the loom to the fuel pump and lights.
Hope this helps.
Cheers
Paul.

[GreenV8S]

Paulathome said:

When you say the car will not start, do you mean the engine turns over and refuses to start or the engine does not turn over?

That's the critical question.

[pupp]

bhpjon said:

pupp said:

One of the three 'cuts' on the immobiliser sounds like it's gone intermittent. Often, it's the starter loop due to the (un-relay assisted) loads switched through it (hence the hot-start mod's effectiveness) but the others fail too. Been there, got the tee-shirt, bypassed the circuit

This seems a new avenue to explore, how do i identify this starter loop, and how would i bypass it please? thanks very much Jonathan

Don't really want to put that up on a public forum but if you fitted the usual hotstart mod you were in the right area Hint: you're looking for three pairs of wires.

PM me if that doesn't point you in the right direction

[bhpjon]

Paulathome said:

Jonathan,
When you say the car will not start, do you mean the engine turns over and refuses to start or the engine does not turn over?
If the engine refuses to turn over then you may have an immobiliser fault as on most TVR's the starter motor circuit is broken when the alarm is armed.
If the engine turns over but you hear no fuel pump then the fuel pump relay may be faulty or the circuit that switches the relay. May be worth changing the relays in the foot well (The two loose ones in the loom by the battery) only cost about a tenner each.
Check under the car (off side near the rear wheel) that the connections are Ok at the pump including the earth.
Also in the drivers side behind the seat, pull back the side panel and check the connectors in there as this is the loom to the fuel pump and lights.
Hope this helps.
Cheers
Paul.

Cheers for that Paul, no the engine does'nt turn over and the fuel pump does not energise. I changed one of the relays after trying swapping them over (which made no difference) I shall now try the next tips in your exhaustive list, cheers Jonathan

[bhpjon]

pupp said:

bhpjon said:

pupp said:

One of the three 'cuts' on the immobiliser sounds like it's gone intermittent. Often, it's the starter loop due to the (un-relay assisted) loads switched through it (hence the hot-start mod's effectiveness) but the others fail too. Been there, got the tee-shirt, bypassed the circuit

This seems a new avenue to explore, how do i identify this starter loop, and how would i bypass it please? thanks very much Jonathan

Don't really want to put that up on a public forum but if you fitted the usual hotstart mod you were in the right area Hint: you're looking for three pairs of wires.

PM me if that doesn't point you in the right direction

You have Mail, Sir!

[pupp]

bhpjon said:

pupp said:

bhpjon said:

pupp said:

One of the three 'cuts' on the immobiliser sounds like it's gone intermittent. Often, it's the starter loop due to the (un-relay assisted) loads switched through it (hence the hot-start mod's effectiveness) but the others fail too. Been there, got the tee-shirt, bypassed the circuit

This seems a new avenue to explore, how do i identify this starter loop, and how would i bypass it please? thanks very much Jonathan

Don't really want to put that up on a public forum but if you fitted the usual hotstart mod you were in the right area Hint: you're looking for three pairs of wires.

PM me if that doesn't point you in the right direction

You have Mail, Sir!

Back at you

[bhpjon]

After about 2 years of suffering at the hands of my electrics, and dozens of replies to my cries for help on pistonheads; Michael from sungold autosounds, newcastle upon tyne, has (it seems!)found the answer to my electrical problems! After a recovery was needed last friday night, the car has remained dead all week so i felt it was about time to tackle this head on. After my engine re-build and replacing lots of the electrical bits on the car, i found (with ribol's help) that there were 2 different issues going on with my car. When hot the starter's solenoid was jamming but sometimes the fuel pump wasn't energising either; but when hot or cold sometimes the power was'nt getting through to the fuel pump which was confusing the issue. Anyway after contemplating getting a new ECU or complete wiring loom to try and correct this most irritating of problems, Michael found the answer;
A B Y LOOSE FUEL PUMP FUSE!!!!!!!!!!!!
It seems it was losing contact for a multitude of reasons, temperature and vibrations being always present in these beautiful yet infuriating motor cars so hopefully i've turned the corner now and can look forward to a few more weeks of carefree motoring before Hibernation kicks in!!

[chr1sb]

Sorry - I'm missing something here. How would a loose fuel pump fuse stop the engine turning over

Edited by chr1sb on Friday 26th October 10:24

[andy-w]

chr1sb said:

Sorry - I'm missing something here. How would a loose fuel pump fuse stop the engine turning over

Edited by chr1sb on Friday 26th October 10:24

along with the lose relays there are a couple of fuses.
i was driving along one day and the car just cut out...came to a halt and when i turned the key there was nothing....it was one of these fuses that had come lose.
It doesnt just feed the fuel pump...

[thegman]

ive been having problems recently:

- fuel pump primes (and all normal electrics)
- nothing from starter motor

this has happened three times. on each occasion I have got into the vehicle after leaving it for 10-15 mins. the temperature has been warm but not hot.

also twice now i have got into my car and somehow re-enabled the alarm, this could be because i am holding down the key fob for too long though. This has coincided with the starting issue at least once but I'm not sure if they are connected.

does this sound like the systems of a hot start problem or an alarm/immobiliser issue?

any way I could tell?

[bhpjon]

chr1sb said:

Sorry - I'm missing something here. How would a loose fuel pump fuse stop the engine turning over

Edited by chr1sb on Friday 26th October 10:24

It does'nt, but the lack of fuel means it won't fire