Big starting trouble - lost for ideas!!

[russelllwilson]

Hi,

Just bought a 1999 Toledo S, 1.8 20v (engine type AGN).
Problem:
1. On a warm day when the car is cold is has trouble starting - I mean it has to turn over 20 to 50 times before it starts! But always starts. (Takes at least 10 to 15 turns when warm)
2. Terrible at idling (constantly hunts around 800rpm when on tic-over)

Here is what I have tried:
1. New temperature control sensor,
2. New MAF
3. Taken car to IVC dealer and tried a diog. check but could not read ECU came up with: "can not read ECU" or "fault reading ECU" but the air bags and and air con could be detected.

IVC man gave me option of: get in an auto electrician (£100 per hour) or new CPU (£800 plus VAT).
I can understant that there may be a wire fault inbetween the diog port and the CPU but surely the CPU can't be broken as the car drives well generally??
Help is needed!!!
Thanks!

 

[Sam20v]

Hi mate, soz to hear bout your probs......
i too have an AGN 1.820v and it idles rough also.......i think i have a small air leak somewhere to the rear of the engine bay, so going to investigate this further.....i am also going to try changing leads and plugs.....hopefully this will smooth it out a bit....will keep you posted.

as for your ECU problem, not sure what to suggest. the dealer you took it too was it Seat?I assume it was some kind of VAGCOM that was plugged in..... if the ECU cant be read then theres a chance it is actually the ECU thats bu66ered. although i would expect performance to go to a limp mode.......unless the diognostic software isnt compatible....not sure, dont know too much bout how the software works...

 

[russelllwilson]

Hey up there,
The dealer I took it to was sn IVC (Independant VW & Audi Company, In Leeds) they had the software to handle the car (so they said?)
Might be worth popping it into a Seat dealer, but thats gonna be another £60ish.
I've scanned loads of other chat rooms and it appears that the AGN engine are prone for idle problems - some people have replaced every sensor they can shake a stick at and the problem was still there?
I'll keep looking around, thanks for the info.
Other general question -
Is it possible to just test the ECU without using the OBD(2) port?

Cheers.

 

[russelllwilson]

An update -
I located the ECU and went to remove it to get the part number to price up a replacement unit. While removing the two leads that fit into the unit it was obvious that the crap location (under the windscreen guttering) was the problem - one of the leades was full of water when I disconnected it. Took it off - cleaned and dried it and now starts like a dream. I'd recommend checking the leads into the ECU if you are experiencing problems!

 

[Sam20v]

Glad you got it sorted mate!
Keep an eye on that!