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Markey Mark (BD)
06-04-2011, 17:51
Right i've done my first F7P conversion in a 5 for myself and have hit a problem, i can't get it to spark. :crap:

I've wired the entire car up and got it kicking over on the key nicely, believe all wires are connected up correctly down under the header tank and run few extra wires for the relays that are attached to the engine loom (fuel pump, fan, water pump, etc).

From start i can't get it to spark, its not AEI unit or power feed to it as i wired timing sensor up like the 5 gt and got it to spark so i'm looking at a signal problem. Also which leads me to signal problem is fuel pump and tacho are not coming on either.

Now the signal wire runs through the ecu, could i be looking at ecu fault, simple wiring fault or have i missed some wires somewhere which won't allow the ecu to see the signal from the timing sensor :confused:

I'm not the best with wiring so bare with me if you have to describe wiring diagrams to me :D

Os8472
06-04-2011, 18:07
If you've got no tacho, no fuel pump and no spark then the ecu isnt seeing the engine turning over, it's a safety feature so if u were to crash the fuel pump wouldn't keep throwing fuel out of the end of the lines.

Which ecu you using?

Markey Mark (BD)
06-04-2011, 18:21
If you've got no tacho, no fuel pump and no spark then the ecu isnt seeing the engine turning over, it's a safety feature so if u were to crash the fuel pump wouldn't keep throwing fuel out of the end of the lines.

Which ecu you using?

Its a standard ecu mate, complete engine cam from a N-reg 96 car.

The timing sensor is ok as tried it wired up like a 5 and the AEI unit sparked, the engine worked fine in the car it come from so can't imagine a wiring fault either as its all within the loom.

Long shot but would thi poss have some sort of built in immobiliser in the ecu?

Bigfoot
06-04-2011, 18:56
The later on cars in the 19 and clio with f7P came with an immobiliser

Scoff
06-04-2011, 19:35
The later on cars in the 19 and clio with f7P came with an immobiliser

Was that in the ECU though ? Those old siemens ECU's are dumb things, I didn't think they had the capacity for an imob.

Mark you need to check that you have lives and earths on all the right pins of the ECU. I remember there being some odditys in the wiring that I didn't expect when I did a conversion for someone years ago. I slept too many times since then to remember what it was though !

Matt@CodeRedMotorsports
06-04-2011, 20:14
No, N reg cars (phase 2) have a decoder unit to authorise the inj comp to unlock. Done via the central locking plip, once you unlock the phase 2 car you have a timed limit before the signal is required again.
If you can borrow a phase 1 clio 16v (around j plate) unit they are non coded.......
Also R19 16v won't work on a clio loom.....believe me tried every combination over the years....;)
Unless it could be that the inj locking relay is not being energised.:scratch:

5teve L
06-04-2011, 20:20
I've been told the Phase 2 ecu are immob & won't work on different cars, not sure if that counts for conversions or if it's in the ecu itself.
Phase 1 ecu should work though.
Mark, the wiring is a little different to the clio but I have a R19 16v ecu you can try mate, I think it's mainly the fuel pump but there is a wiring guide in this section I found that translate from German mate.

Markey Mark (BD)
06-04-2011, 22:51
No, N reg cars (phase 2) have a decoder unit to authorise the inj comp to unlock. Done via the central locking plip, once you unlock the phase 2 car you have a timed limit before the signal is required again.
If you can borrow a phase 1 clio 16v (around j plate) unit they are non coded.......
Also R19 16v won't work on a clio loom.....believe me tried every combination over the years....;)
Unless it could be that the inj locking relay is not being energised.:scratch:

Matt so is it worth trying an early ecu on the engine then? I know there is a difference in the wiring looms from early to late cars so will it be ok to swap late ecu for early one? Or is there a way of wiring round the ecu's lock on the inj comp?

Scoff, i think i have them all right and would check them but i can't make out what number the pins are on the ecu plug. The Haynes manual diagrams were hard enough to follow and without a numbered plug i'm little buggered. :laugh:

Think once i have this all sorted i'll be noting it all down for future reference.

Scoff
06-04-2011, 23:03
Ah, I didn't know about the imo on the later ECU's, good info :)

Matt@CodeRedMotorsports
06-04-2011, 23:11
Matt so is it worth trying an early ecu on the engine then? I know there is a difference in the wiring looms from early to late cars so will it be ok to swap late ecu for early one? Or is there a way of wiring round the ecu's lock on the inj comp?

Scoff, i think i have them all right and would check them but i can't make out what number the pins are on the ecu plug. The Haynes manual diagrams were hard enough to follow and without a numbered plug i'm little buggered. :laugh:

Think once i have this all sorted i'll be noting it all down for future reference.

Yes you can retro fit an early ecu to a later car.
If you get into trouble, I have an early non coded ecu you can borrow, its fitted with an R-Tuner re-mappable chip which will pose no probs with just starting the car.
OR, another superchipped non coded unit you can borrow if need be.
Matt

Markey Mark (BD)
06-04-2011, 23:33
Yes you can retro fit an early ecu to a later car.
If you get into trouble, I have an early non coded ecu you can borrow, its fitted with an R-Tuner re-mappable chip which will pose no probs with just starting the car.
OR, another superchipped non coded unit you can borrow if need be.
Matt

Ah brilliant mate, that would get me out of trouble.

If its a simple case of swaping the ECU's i got a mate who may have one to borrow but would prefer to find replacement if have to swap ecu's. This ecu i have is meant to be chipped too but how i don't know myself.

Also thinking about it youmentioned the inj comp relay, is that one of those brown relays that is the same as the fuel pump, fan, etc or is it the larger black relay? I can check those just to make sure they are wired up correctly and sending power out.

Markey Mark (BD)
10-04-2011, 17:18
It runs! :D

Swapped ECU for early phase 1 unit and got spark straight away. So looks like ohase 2 ecus do have some sort of built-in immobiliser, bit of usfull info for anyone else doing the conversion.