S4 will not run
01-01-2008, 04:24 AM
#31
From the top of my head, I would say yes, there is a difference. LH will go into a loop mode w/o O2 sensor. There is a plug on LH board in US made cars used as jumper to compensate for O2 sensor, I will look into manuals to tell u more .
01-01-2008, 04:30 AM
#32
Advanced
Thread Starter
Join Date: Aug 2004
Location: Sydney, Australia
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
I think its time for me to get the workshop manuals.
01-01-2008, 06:02 AM
#33
Nordschleife Master
An alternativel to a CO meter is to adjust the pot to the standard bosch spec. for resistance, 0.380 kohms, which will get you pretty close. You can test the resistance on pins 1 and 2 of the pot (it has 3 pins.. numbers are on the side of the plastic connector surround). Its much easier to test/adjust on the bench removed from the car.
Taking the car to a decent workshop with a CO meter is sitll the best option.
01-01-2008, 06:46 AM
#34
Rennlist Member
There is no difference in the LH ECU for cat ort non-cat. The LH is made to run in either state by the code plug
Make sure you plugged that 8 way coding plug back in when you refitted the LH ECU into the car. If it is left disconnected, the car will run very rich. It should be clipped to the plate that holds the LH and EZK ECUs. Sometimes it hands loose. The socket is on the cableform, the plug on the plate.
It is most unlikely the LH ECU is faulty.
Make sure you plugged that 8 way coding plug back in when you refitted the LH ECU into the car. If it is left disconnected, the car will run very rich. It should be clipped to the plate that holds the LH and EZK ECUs. Sometimes it hands loose. The socket is on the cableform, the plug on the plate.
It is most unlikely the LH ECU is faulty.
01-01-2008, 07:14 AM
#35
Advanced
Thread Starter
Join Date: Aug 2004
Location: Sydney, Australia
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
Hi Akram,
An alternativel to a CO meter is to adjust the pot to the standard bosch spec. for resistance, 0.380 kohms, which will get you pretty close. You can test the resistance on pins 1 and 2 of the pot (it has 3 pins.. numbers are on the side of the plastic connector surround). Its much easier to test/adjust on the bench removed from the car.
Taking the car to a decent workshop with a CO meter is sitll the best option.
An alternativel to a CO meter is to adjust the pot to the standard bosch spec. for resistance, 0.380 kohms, which will get you pretty close. You can test the resistance on pins 1 and 2 of the pot (it has 3 pins.. numbers are on the side of the plastic connector surround). Its much easier to test/adjust on the bench removed from the car.
Taking the car to a decent workshop with a CO meter is sitll the best option.
There is no difference in the LH ECU for cat ort non-cat. The LH is made to run in either state by the code plug
Make sure you plugged that 8 way coding plug back in when you refitted the LH ECU into the car. If it is left disconnected, the car will run very rich. It should be clipped to the plate that holds the LH and EZK ECUs. Sometimes it hands loose. The socket is on the cableform, the plug on the plate.
It is most unlikely the LH ECU is faulty.
Make sure you plugged that 8 way coding plug back in when you refitted the LH ECU into the car. If it is left disconnected, the car will run very rich. It should be clipped to the plate that holds the LH and EZK ECUs. Sometimes it hands loose. The socket is on the cableform, the plug on the plate.
It is most unlikely the LH ECU is faulty.
I didn't suspect the ECU to be faulty, the car actually runs but can't hold idle and there is a lot of smoke and fuel smell. When I took off the LH/EZK plate, there was nothing attached to it. I could see some connectors (plastic) behind the plate, but not connected it at all
Does this connector need to be grounded via the plate?
01-01-2008, 08:05 AM
#36
Advanced
Thread Starter
Join Date: Aug 2004
Location: Sydney, Australia
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
There is no difference in the LH ECU for cat ort non-cat. The LH is made to run in either state by the code plug
Make sure you plugged that 8 way coding plug back in when you refitted the LH ECU into the car. If it is left disconnected, the car will run very rich. It should be clipped to the plate that holds the LH and EZK ECUs. Sometimes it hands loose. The socket is on the cableform, the plug on the plate.
It is most unlikely the LH ECU is faulty.
Make sure you plugged that 8 way coding plug back in when you refitted the LH ECU into the car. If it is left disconnected, the car will run very rich. It should be clipped to the plate that holds the LH and EZK ECUs. Sometimes it hands loose. The socket is on the cableform, the plug on the plate.
It is most unlikely the LH ECU is faulty.
[edit]
The socket is connected to the plug (but not through the plate), that should be OK, right?
https://rennlist.com/forums/attachme...1&d=1199188718
Last edited by touay001; 01-01-2008 at 08:30 AM. Reason: Added more info
01-01-2008, 08:53 AM
#37
Advanced
Thread Starter
Join Date: Aug 2004
Location: Sydney, Australia
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
01-01-2008, 08:57 AM
#38
Rennlist Member
It's OK for it to be not mounted on the plate. It is not grounded to the plate.
You should find the flying socket coming out of the cable form with the plug inserted into it.
You have fitted a rebuilt MAF. It is possible that previously the idle mixture pot above the centre of the fuse/relay panel has been turned up to maximum (1000 ohms).
If you disconnect the LH ECU 35 way plug, and probe pin 23 (CO pot) and pin 5 (ground) with an ohmeter, and adjust to around 300 ohms as Hilton says. You may find it easier to measure at the 35 way than on the pot connector.
Or you could just try turning 10 turns anticlockwise as you suggest to see if there is an improvement, but the better methode is to measure the resistance if possible.
You should find the flying socket coming out of the cable form with the plug inserted into it.
You have fitted a rebuilt MAF. It is possible that previously the idle mixture pot above the centre of the fuse/relay panel has been turned up to maximum (1000 ohms).
If you disconnect the LH ECU 35 way plug, and probe pin 23 (CO pot) and pin 5 (ground) with an ohmeter, and adjust to around 300 ohms as Hilton says. You may find it easier to measure at the 35 way than on the pot connector.
Or you could just try turning 10 turns anticlockwise as you suggest to see if there is an improvement, but the better methode is to measure the resistance if possible.
01-01-2008, 09:08 AM
#39
Advanced
Thread Starter
Join Date: Aug 2004
Location: Sydney, Australia
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
It's OK for it to be not mounted on the plate. It is not grounded to the plate.
You should find the flying socket coming out of the cable form with the plug inserted into it.
You have fitted a rebuilt MAF. It is possible that previously the idle mixture pot above the centre of the fuse/relay panel has been turned up to maximum (1000 ohms).
If you disconnect the LH ECU 35 way plug, and probe pin 23 (CO pot) and pin 5 (ground) with an ohmeter, and adjust to around 300 ohms as Hilton says. You may find it easier to measure at the 35 way than on the pot connector.
Or you could just try turning 10 turns anticlockwise as you suggest to see if there is an improvement, but the better methode is to measure the resistance if possible.
You should find the flying socket coming out of the cable form with the plug inserted into it.
You have fitted a rebuilt MAF. It is possible that previously the idle mixture pot above the centre of the fuse/relay panel has been turned up to maximum (1000 ohms).
If you disconnect the LH ECU 35 way plug, and probe pin 23 (CO pot) and pin 5 (ground) with an ohmeter, and adjust to around 300 ohms as Hilton says. You may find it easier to measure at the 35 way than on the pot connector.
Or you could just try turning 10 turns anticlockwise as you suggest to see if there is an improvement, but the better methode is to measure the resistance if possible.
The positive thing about this, is that I get to learn how the system works.
01-01-2008, 10:45 AM
#40
Rennlist Member
The pot is only 20 turns end to end, but there are no end stops, so it is possible for someone to turn beyond the end previously. So it might take 5 turns just to get it "back onto track". The pots can be damaged by excessive turning against their stops.
If the car is running very rich even from a cold start, this suggests some other problem. Like temp sensor 2, code plug off, CO pot open circuit etc.
If the car is running very rich even from a cold start, this suggests some other problem. Like temp sensor 2, code plug off, CO pot open circuit etc.
01-02-2008, 01:35 AM
#41
Advanced
Thread Starter
Join Date: Aug 2004
Location: Sydney, Australia
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
Update
I worked on the car all day today trying to figure out the running problem. That's what I did today:
The car still runs very rich and wont idle without pressing the accelerator. I don't know what else I can do. Any ideas?
I worked on the car all day today trying to figure out the running problem. That's what I did today:
- Checked the CO2 pot and it was 337 ohm (after the 10 turns I did yesterday)
- Checked Temp II ~ 2 k @ 30C ???
- Checked CO2 and Temp II sensor from the LH connector OK
- Cleaned all ground points
- Changed the spark plugs (again)
The car still runs very rich and wont idle without pressing the accelerator. I don't know what else I can do. Any ideas?
01-02-2008, 01:56 AM
#42
Race Director
The temp II sender is within range, but did you test both pins...1 is for the LH the other for the EZK? They should be the same reading....however you problem seems to be fuel not spark so I would guess the EZK side is fine....
Since it won't idle it makes me think the idle stabilizer....but that won't account for the rich running?
he proper Temp Sensor II resistance measurements are:
0 C / 32 F: 4.4k to 6.0k Ohms
15 - 30 C / 59 - 86 F: 1.4k to 3.6k Ohms
40 C / 104 F: 0.9 to 1.3k Ohm
60 C / 140 F: 480 to 720 Ohms
80 C / 176 F: 250 to 390 Ohm
Since it won't idle it makes me think the idle stabilizer....but that won't account for the rich running?
he proper Temp Sensor II resistance measurements are:
0 C / 32 F: 4.4k to 6.0k Ohms
15 - 30 C / 59 - 86 F: 1.4k to 3.6k Ohms
40 C / 104 F: 0.9 to 1.3k Ohm
60 C / 140 F: 480 to 720 Ohms
80 C / 176 F: 250 to 390 Ohm
01-02-2008, 02:06 AM
#44
Advanced
Thread Starter
Join Date: Aug 2004
Location: Sydney, Australia
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
I followed the procedure on the above site. That's all what I can do without specialized test equipment. I'm waiting for a SPANNER to arrive in the next couple of days. In the mean time, I'll be looking for mechanical issues (air leaks, fuel dumpers,...)
01-02-2008, 02:09 AM
#45
Race Director
I keep thinking its the MAF causing an odd limp home feature causing the rich condition.... or a combo MAF-LH thing..... but you've checked all of those?
It does seem something is causing the injectors to fire too much.....but why....the new LH didn't help?? I can't think of anything in the fuel system that would fail and cause TOO much fuel..... Have you checked the dampers to see if they hold vacumm and don't squirt gas.....same for the pressure regulator.....but I thought when the regulator fails it just sends too much gas back to the tank......