SEAT IBIZA - Dead as a doornail

pvt

I did buy a cheap code reader, and it says it cannot communicate with the ECU - I assumed it was too cheap and didn't understand the VAG protocols, but I wonder now if it is the issue khcomp suggests - a dead ECU. But I just wouldn't expect the engine warning lamp to operate if the ECU was completely stiffed.

Angrycrow, you refer to the crankshaft position sensor - I didn't realise there was one - I thought the timing was done via the camshaft sensor?

I can see ECUs for sale on eBay - but they seems to always come with the dashboard unit, and locks and keys etc. Do I assume from that you have to change all of these together, and cannot just replace an ECU by itself?

Have already tried a battery disconnect - no joy.

reeac

angrycrow wrote: »

Engine cutting out and then being difficult to start when hot is often a sign of a failing crank position sensor. When the sensor fails the ecu does not get the timing signal to fire the plugs so no spark.

My only experience with a failing crankshaft position sensor was poor starting from cold. I assumed that the lowered battery voltage during cold cranking showed up the cps problem. Once started and running there were no detectable problems.

onomatopoeia99

Know anyone local to you with VCDS (vagcom as it used to be known) ? Though if you can't get a cheap code reader to work you may not get anything from it.

agrinnall

Given that you have no spark at any of the plugs it's almost certainly not this, but my 2002 Leon suffered from coil failure, which the recovery guy said was commonplace in VAG cars after they switched from a Japanese coil supplier to a German one to save money.

pvt

agrinnall wrote: »

Given that you have no spark at any of the plugs it's almost certainly not this, but my 2002 Leon suffered from coil failure, which the recovery guy said was commonplace in VAG cars after they switched from a Japanese coil supplier to a German one to save money.

Yes - all 4 of the original VW ones have been replaced at various times due to failure - the originals were cr4p. All 4 are now Japanese NGK ones, which Lloyds tell me they have never heard of any failing. So I'm confident it's not these at fault.

pvt

onomatopoeia99 wrote: »

Know anyone local to you with VCDS (vagcom as it used to be known) ? Though if you can't get a cheap code reader to work you may not get anything from it.

My plan is to replace the camshaft sensor - it's only £25 - and if that isn't the answer I'll pay for a grown up to come and plug a proper VAG compatible diagnostic unit in.

When I crank it I notice there doesn't appear to be any smell of fuel either - so wondering if the injectors are also not being fired by the ECU, so I'm now beginning to suspect the ECU has rolled over and stuck its legs in the air.

joeblags

there have been cases of fuses popping aswell and even relays going bad. ive had just about every problem on my seat inc an immob that wouldn't recode so I just had it remove from the ecu! on my current seat I had to replace the whole loom for the engine to even get my car going. another problem I suffered but managed to get to in time, is there any water leaking down behind the seal at the bottom on the window? your ecu will be here and if could over time if there is a leak give some pretty bad corrosion on the pins.

pvt

joeblags wrote: »

there have been cases of fuses popping aswell and even relays going bad. ive had just about every problem on my seat inc an immob that wouldn't recode so I just had it remove from the ecu! on my current seat I had to replace the whole loom for the engine to even get my car going.

I'll check the fuses - hadn't thought of that.

When you replaced the wiring loom did you perform a post mortem on the old one and find any evidence of where the fault was?

joeblags

pvt wrote: »

I'll check the fuses - hadn't thought of that.

When you replaced the wiring loom did you perform a post mortem on the old one and find any evidence of where the fault was?

I did find lots of the connections on the plugs was in a sory state but it wasn't them causing my problem, it was were the engine loom connected to the loom that joins the loom that enters the car, I also had bad earths lol, under the battery tray is were the connection is located or is on my car. that was seriously corroded to the point I either had to chop and join all the cables and bypass the plugs or buy a new loom.


http://www.seatcupra.net/forums/


youll get all sorts if replys on there, inc people offering wiring loom diagrams. I wouldn't pay for somebody with ross tech to scan your car as you might be wasting money, even a cheapo one should be connecting , can you confirm by scanning somebody elses car the scanner is ok?

Geoff1963

But I just wouldn't expect the engine warning lamp to operate if the ECU was completely stiffed.

It probably defaults to on, if it doesn't get an "I'm OK" message from the Engine ECU.