Missfire?..Help :(

Missfire?..Help :(

Author
Discussion

MartS1

Original Poster:

147 posts

249 months

Saturday 20th September 2003
quotequote all
My S1 (2.9 not 2.8)has just started to hesitate sometimes, only under load tho
All the rotor arm, dizzy cap, plugs etc seem to be ok, has anyone got any ideas?
Mart

>>> Edited by MartS1 on Saturday 20th September 11:01

Colin BlueS2

2,527 posts

258 months

Saturday 20th September 2003
quotequote all
If it's a 2.9 then...... altogether now.

Throttle Pot.

Is it hestitating when you put your foot down if so then the TP has to be a prime candidate. They are notorious for failing. Their job is to read what your right foot is doing and tell the ECU to put in the appropriate fuel. The tracks on them waer over time and lead to spurious readings which confuse the hell out of the ECU.

Colin

MartS1

Original Poster:

147 posts

249 months

Saturday 20th September 2003
quotequote all
Any ideas on where i can get one, or is there a way of fixing my existing one?
Thanks
Mart

Colin BlueS2

2,527 posts

258 months

Saturday 20th September 2003
quotequote all
Your freindly Ford dealer can help. I don't believe they are repairable. I think Ford now only sell the 'gold contact' version which is supposed to be more reliable, but you need to get the new plug and wiring that goes with it. This needs to be put in place of the existing one, and it needs to be connected differently. I can't remember how it goes now, but if you do a search on the forum for throttle pot there are several posts on how to connect it up. The part number is on the parts guide, on here.

Godd luck.

Colin

shnozz

27,502 posts

272 months

Saturday 20th September 2003
quotequote all
agreed. you can try unplugging it first and it will go into the "safe mode" and then drive it to see if you still get any probs. If not, go buy a new one.

MartS1

Original Poster:

147 posts

249 months

Saturday 20th September 2003
quotequote all
Might sound a bit dim but which bit is the throttle pot
Is it where the two pipes from the Air Flow meters join?
On the side of that bit i have a black cylinder thing thats not connected to anything! Should it be connected?
Mart

markbigears

2,275 posts

270 months

Saturday 20th September 2003
quotequote all
mart, i had this problem in my old porsche.....under load, ie: as i went to overtake!!! the car just sluttered. Very dangerous. I found by looking at the car in the dark i could see a very small spark every 2 mins or so between the fuel injector and the lead.
Replaced leads and injector and the problem went. Might be worth a try just having the car in the dark to see if you can see any random shorts. This type of problem is very frustrating i know cos it can be any number of things breaking down.

Colin BlueS2

2,527 posts

258 months

Saturday 20th September 2003
quotequote all
Yes

You should have the throttle pot which is usually a black plastic thingy attached to the other end of the thottle spindle that passes through the plenum chamber. Also nearby is the idle speed control valve which is like a horizontally mounted cylinder. Both of these should be connected up to the loom.

Have a look in the Bible on page 58.

Colin

MartS1

Original Poster:

147 posts

249 months

Saturday 20th September 2003
quotequote all
My Bible has not turned up yet
Dont suppose anyone can take a piccy and mail it to me?
Thanks for all your help
Suppose this is why the car feels slow??
Do they all have two air flow meters at the front of the car? Mine has
Mart

Colin BlueS2

2,527 posts

258 months

Saturday 20th September 2003
quotequote all
Try this



Colin

MartS1

Original Poster:

147 posts

249 months

Saturday 20th September 2003
quotequote all
Thanks colin
The Idle valve is definatley not connected, i dont even know where the wire is for that
Not sure about the other bit, i will have a look when i get home
Thanks Again
Martyn

marts1

Original Poster:

147 posts

249 months

Saturday 20th September 2003
quotequote all
Big thanks to Colin, I think i have it sorted now
Mart