325 cabby over running rich
Moderator: martauto
- gingerrusta
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Hi guys
Decided to get a few things done on my cabby with the following
All being done
New dizzy
New rotor
New plugs ngk
New air filter k and n
New water pump
New belts
Now when all done she doesn't seem to be running very well
Tick over is a bit up and down
She is using a lot of fuel I think
Old plugs were black
I took off the rubber boot between AFM and throttle body and that seems ok
The throttle body looked a little dirty inside so cleaned that a little
I got a new blue temp sensor but that is in a position I can't get a spanner or socket to ? Is that normal or am I missing something ?
Any ideas ? She has been stood around for a bit .
I have a video of tick over but am unsure how to upload it
Decided to get a few things done on my cabby with the following
All being done
New dizzy
New rotor
New plugs ngk
New air filter k and n
New water pump
New belts
Now when all done she doesn't seem to be running very well
Tick over is a bit up and down
She is using a lot of fuel I think
Old plugs were black
I took off the rubber boot between AFM and throttle body and that seems ok
The throttle body looked a little dirty inside so cleaned that a little
I got a new blue temp sensor but that is in a position I can't get a spanner or socket to ? Is that normal or am I missing something ?
Any ideas ? She has been stood around for a bit .
I have a video of tick over but am unsure how to upload it
- Brianmoooore
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Have you tested the blue temp sensor at the ECU plug?
- gingerrusta
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I haven't . How would I do this ?
- gingerrusta
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At the top of the page in the section of the forum called wiki. Then from there follow the technical section for engine. It's covered in there.
As for replacing the sensor, if your tests confirm the wiring is ok but the sensor is duff you will need to remove the fuel pressure regulator to get access to the blue sensor to remove it.
You will also need a deep 19mm socket from what I remember.
As for replacing the sensor, if your tests confirm the wiring is ok but the sensor is duff you will need to remove the fuel pressure regulator to get access to the blue sensor to remove it.
You will also need a deep 19mm socket from what I remember.
- gingerrusta
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If you click the link you will see its to the left of the picture
And is hard to get to ?
And is hard to get to ?
- Brianmoooore
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http://www.e30zone.net/e30zonewiki/inde ... or#Testinggingerrusta wrote:I haven't . How would I do this ?
BUT the info. is the wrong way around. Always test at the ECU pins first. The ECU pins depend on what engine/ECU you have, but the ones given in the wiki are right for 55 pin M20 ECUs.
Blue sensor can be removed without moving anything else, with the right tools, but is easier with the brown sensor removed first.
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Brain what tools would you suggest. When I did mine even with the brown sensor out the way it was near impossible to get a spanner on it including a swan neck one. With the FPR out the way getting a socket on it was much easier.
Only thing I could think of which I didn't have at the time was a cut down box spanner and an adjustable wrench.
Only thing I could think of which I didn't have at the time was a cut down box spanner and an adjustable wrench.
- gingerrusta
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Honestly I took brown sensor out and even brought a flexy
Head 19mm ratchet and it still wouldn't work.
I have changed one Before on a 320 which was easy. I think
There must be some variants on them 6 cyl engines.
Head 19mm ratchet and it still wouldn't work.
I have changed one Before on a 320 which was easy. I think
There must be some variants on them 6 cyl engines.
- gingerrusta
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I'm sorry to sound a bit clueless but when testing at the ecu
You take off the main wiring clip and then find the pins you need to check ?
Is this done with the ignition on ?
You take off the main wiring clip and then find the pins you need to check ?
Is this done with the ignition on ?
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Ignition off and the big wiring plug disconnected.
- gingerrusta
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Ok cool and my multimeter looks like it only displays a 1 when showing
Anything over 2000. Is that ok or do I need to use a better one?
Anything over 2000. Is that ok or do I need to use a better one?
- Brianmoooore
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Ignition off. Take the 55 pin plug off of the ECU and identify the pins you need. A permanent marker is useful.
Measure the resistance with the engine cold, then refit the plug, start and bring the engine up to full temperature, stop the engine, disconnect it again, and quickly measure the resistance again before the engine starts to cool.
Be careful not to spread the contacts of the buckets in the plug by forcing the meter probes into them. A couple of 1" lengths of 15A fusewire can be pushed into the plug, and the probes attached to the fusewire.
You may find it easier to unscrew the ECU from its bracket to get the plug off. It's OK to run the engine with the ECU hanging on its wire
Measure the resistance with the engine cold, then refit the plug, start and bring the engine up to full temperature, stop the engine, disconnect it again, and quickly measure the resistance again before the engine starts to cool.
Be careful not to spread the contacts of the buckets in the plug by forcing the meter probes into them. A couple of 1" lengths of 15A fusewire can be pushed into the plug, and the probes attached to the fusewire.
You may find it easier to unscrew the ECU from its bracket to get the plug off. It's OK to run the engine with the ECU hanging on its wire
- Brianmoooore
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Presumably '1' is your meter's over range indication. It should show this with the leads not connected to anything, and 0.00 if you touch the probes together.gingerrusta wrote:Ok cool and my multimeter looks like it only displays a 1 when showing
Anything over 2000. Is that ok or do I need to use a better one?
I've never see n a meter, even a cheap one, that can't read more than 2000 ohms. You should have several ranges with multipliers, such as X1, X10, X100, etc., or just showing the maximum for each range, such as 200, 2k, 20k, etc.
- gingerrusta
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You put the red prong on the pin and the black on an earth ?
- gingerrusta
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Brianmoooore wrote:Presumably '1' is your meter's over range indication. It should show this with the leads not connected to anything, and 0.00 if you touch the probes together.gingerrusta wrote:Ok cool and my multimeter looks like it only displays a 1 when showing
Anything over 2000. Is that ok or do I need to use a better one?
I've never see n a meter, even a cheap one, that can't read more than 2000 ohms. You should have several ranges with multipliers, such as X1, X10, X100, etc., or just showing the maximum for each range, such as 200, 2k, 20k, etc.
It has listed on it
2000k
200k
20k
2000 ( with an arrow and + sign joined together )
200.
Which one would I have it on for testing ?
- Brianmoooore
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You start with it on 200, and then increase it one step at a time, until the '1' over range indication changes to a reading. For a good sensor and wiring, this will be 2000 for the hot test and 20k for the cold.
- gingerrusta
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Thank you for the replies brianmoooore .
So turn meter on and start with it on 200
Ignition off
The prongs on the blue temp socket
Looking for between 3500 - 4000
Reconnect, warm up the engine, and retest
Then looking for 330
Locate the ECU and disconnect its plug.
Repeat the Blue Plug test, this time putting your multimeter electrodes onto pins 24 and 45 of ecu
So turn meter on and start with it on 200
Ignition off
The prongs on the blue temp socket
Looking for between 3500 - 4000
Reconnect, warm up the engine, and retest
Then looking for 330
Locate the ECU and disconnect its plug.
Repeat the Blue Plug test, this time putting your multimeter electrodes onto pins 24 and 45 of ecu
- Brianmoooore
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Wrong way around. Do the test at the ECU socket first.
When testing anything electrical it's important not to disturb the suspect part, as that may make the fault go away, only for it to return later. For instance, the fault might be at the connection between the injector loom and the engine loom, and reaching in and unplugging the connector to the blue sensor could disturb that connection and temporarily cure it. The blue sensor might be fragile with age, and unplugging its connector might have cracked it internally.
Your tests will now show up what was a perfectly serviceable blue sensor as being faulty, but the problem with the connection in the loom will go undetected. You will replace the blue sensor with new, and all will be well, until the loom connection fails again, at which point you will be back where you started.
If you had tested at the ECU plug, well away from the location of the fault, you would have discovered the real fault right from the start.
When testing anything electrical it's important not to disturb the suspect part, as that may make the fault go away, only for it to return later. For instance, the fault might be at the connection between the injector loom and the engine loom, and reaching in and unplugging the connector to the blue sensor could disturb that connection and temporarily cure it. The blue sensor might be fragile with age, and unplugging its connector might have cracked it internally.
Your tests will now show up what was a perfectly serviceable blue sensor as being faulty, but the problem with the connection in the loom will go undetected. You will replace the blue sensor with new, and all will be well, until the loom connection fails again, at which point you will be back where you started.
If you had tested at the ECU plug, well away from the location of the fault, you would have discovered the real fault right from the start.
- gingerrusta
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Done the test today with my meter and found the following :
Engine cold
Ecu
Meter on 200.
1
Meter on 2000arrowplus sign
1369
Meter on 20k
1.44
Meter on 200k
0.15
Meter on 2000k
002
Blue sensor plug
Meter on 200
1
Meter on 2000arrowplus sign
1033
Meter on 20k
-7.25
Meter on 200k
69.1
Meter on 2000k
-688
Car was not idling well and cutting out
Engine warm
Ecu readings in same order
1
1277
1.45
0.15
002
Blue sensor plug in same order
1
1025
-7.23
-69.0
-679
Does this make sense to you Brian moooore
Engine cold
Ecu
Meter on 200.
1
Meter on 2000arrowplus sign
1369
Meter on 20k
1.44
Meter on 200k
0.15
Meter on 2000k
002
Blue sensor plug
Meter on 200
1
Meter on 2000arrowplus sign
1033
Meter on 20k
-7.25
Meter on 200k
69.1
Meter on 2000k
-688
Car was not idling well and cutting out
Engine warm
Ecu readings in same order
1
1277
1.45
0.15
002
Blue sensor plug in same order
1
1025
-7.23
-69.0
-679
Does this make sense to you Brian moooore
- gingerrusta
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Bump
- Brianmoooore
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Frankly, not a lot! The first group could be those from a partly warm engine, but after that they are all far from what they should be, and I don't understand how you are getting minus readings. The only way this can happen on a resistance range is if there is a voltage present, confusing the meter.gingerrusta wrote:
Does this make sense to you Brian moooore
I think you may be doing something wrong.
- gingerrusta
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The car was cold as it hasn't been run for 24 hours
I was confused how I got the minus ones.
What would you suggest ? Car is cold and hasn't been run today
I take it the pins start from left to right on the ecu and then onto the next row below
I was confused how I got the minus ones.
What would you suggest ? Car is cold and hasn't been run today
I take it the pins start from left to right on the ecu and then onto the next row below
- gingerrusta
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Could the voltage maybe something to do with the Clifford alarm ?
- Brianmoooore
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Pin #1 is bottom right when the ECU is the right way up. E30s mount it upside down, so #1 is top left as it sits in the car.
The numbers at the ends of the rows are marked in the ECU's socket.
The numbers at the ends of the rows are marked in the ECU's socket.
- gingerrusta
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I done it bolted in the car taking top left as number 1
- gingerrusta
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So what would you suggest I do now ?
- Brianmoooore
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Are you sure you 'transferred' the pin positions to the face of the plug properly? #1 in the top right corner if you swing the plug back horizontally.
- gingerrusta
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I unplugged the black plug from the ecu by pulling the silver clip and moving the connector out of the way.
The ecu was not unbolted and kept in its normal position
I counted the pins in the ecu starting from the top row on left hand side
I marked the 2 pins 24 and 45 with marker pen as to not test the incorrect ones.
I tested the pins on the ecu . Was I meant to test the pins on the ecu plug?
If this is where I have gone wrong I am a tit
The ecu was not unbolted and kept in its normal position
I counted the pins in the ecu starting from the top row on left hand side
I marked the 2 pins 24 and 45 with marker pen as to not test the incorrect ones.
I tested the pins on the ecu . Was I meant to test the pins on the ecu plug?
If this is where I have gone wrong I am a tit
- Brianmoooore
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I think we may have found the problem!
- gingerrusta
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Lol I will re do the test on the plug then
That is probably why the strange - readings
I will redo the test starting at the ecu plug
Question
Testing at plug ecu end first do you test it there first and then reconnect it to the ecu before testing the blue temp sensor end ?
Just to doubley make sure

That is probably why the strange - readings
I will redo the test starting at the ecu plug
Question
Testing at plug ecu end first do you test it there first and then reconnect it to the ecu before testing the blue temp sensor end ?
Just to doubley make sure

- gingerrusta
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Also does it matter what side you put the meter red and black pins on?
- Brianmoooore
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Won't make any difference whether the ECU plug is back on or not, since it's the blue sensor you're supposed to be testing, not its plug!
You also shouldn't have gone anywhere near the blue sensor at all, until the results at the ECU plug have been evaluated. The whole idea, with any electrical testing, is not to disturb what you suspect to be faulty, before you have proven it to be faulty, in case disturbing it provides a cure, only for the fault to return at a later date.
You also shouldn't have gone anywhere near the blue sensor at all, until the results at the ECU plug have been evaluated. The whole idea, with any electrical testing, is not to disturb what you suspect to be faulty, before you have proven it to be faulty, in case disturbing it provides a cure, only for the fault to return at a later date.
- gingerrusta
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So test ecu plug
And blue temp sensor pins and not the plug
And blue temp sensor pins and not the plug
- gingerrusta
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Now I have probably done something I shouldn't of.
I replaced the blue temp sensor tonight and she now struggles ticking over and cuts out.
She has gone the opposite of over fuelling .
What would you suggest to do now ?
I replaced the blue temp sensor tonight and she now struggles ticking over and cuts out.
She has gone the opposite of over fuelling .
What would you suggest to do now ?