car running rich/anyway to adjust mixture
12-06-2002, 03:19 PM
#1
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car running rich/anyway to adjust mixture
my 85.5 is running way to rich after timing change and maf change.can this be adjusted/whats wrong with it. <img src="graemlins/xyxwave.gif" border="0" alt="[bigbye]" />
12-06-2002, 11:39 PM
#2
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Angelo -
There is a way to do so but I'm not going to try to explain. I'm not too familiar and It's like having a blind man lead you across a busy intersection - Just not prudent.
You will need a CO meter and a special tool to dial in the MAF. After the protective plate has been removed if it hasn't been already.
In retrospect -
I think the basic steps are to
1. Disconnecting the smog pump tube and blocking it
2. Adjusting the "big Screw" on the Throttle Body
3. Adjusting the MAF accordingly. To the right is richer and to the left is leaner?. Little Help here Shark Mates.
I'm sorry I'm not more helpful, but at least you have an idea of what's involved.
BTW - Do you disconnect the battery terminals during the TB job?. In not, disconnect the battery terminals and rehooked them after 10 minutes or so?. This may help the ECU adjust accordingly.
Please, I just would like to say that this information was gained by research, trial and error. If any of this information is incorrect, I apologize. I'm still using my learning curve!Please wait or ask for a "sure thing" such as from the man himself - Wally P.
Good Luck -
There is a way to do so but I'm not going to try to explain. I'm not too familiar and It's like having a blind man lead you across a busy intersection - Just not prudent.
You will need a CO meter and a special tool to dial in the MAF. After the protective plate has been removed if it hasn't been already.
In retrospect -
I think the basic steps are to
1. Disconnecting the smog pump tube and blocking it
2. Adjusting the "big Screw" on the Throttle Body
3. Adjusting the MAF accordingly. To the right is richer and to the left is leaner?. Little Help here Shark Mates.
I'm sorry I'm not more helpful, but at least you have an idea of what's involved.
BTW - Do you disconnect the battery terminals during the TB job?. In not, disconnect the battery terminals and rehooked them after 10 minutes or so?. This may help the ECU adjust accordingly.
Please, I just would like to say that this information was gained by research, trial and error. If any of this information is incorrect, I apologize. I'm still using my learning curve!Please wait or ask for a "sure thing" such as from the man himself - Wally P.
Good Luck -
12-07-2002, 10:57 AM
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Angelo,
Check TCII (water temp sender) and TCI (air temp sender).
Perhaps your MAF is bad. Install a known to be good MAF in your car to see. When mine failed, car ran extremely rich, could not drive it. Meanwhile, my MAF passed the shop manual tests. The rebuilt unit from Vertex I installed was better but still bad (I returned it). A new unit solved the problem. I have since learned that there are alot of bad rebuilders out their. The operating spec appears to be very tight. See <a href="http://www.jdsporsche.com" target="_blank">www.jdsporsche.com</a> for great info. He seems very capable.
Good luck.
Check TCII (water temp sender) and TCI (air temp sender).
Perhaps your MAF is bad. Install a known to be good MAF in your car to see. When mine failed, car ran extremely rich, could not drive it. Meanwhile, my MAF passed the shop manual tests. The rebuilt unit from Vertex I installed was better but still bad (I returned it). A new unit solved the problem. I have since learned that there are alot of bad rebuilders out their. The operating spec appears to be very tight. See <a href="http://www.jdsporsche.com" target="_blank">www.jdsporsche.com</a> for great info. He seems very capable.
Good luck.
12-07-2002, 09:53 PM
#6
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Angelo said:
"my 85.5 is running way to rich after timing change and maf change.can this be adjusted/whats wrong with it."
I don't really know what an "85.5" is, but the timing on a USA 32-valve '85 engine isn't adjustable. This almost certainly means that Angelo has a 16-valve RoW car with K-Jetronic, not the LH-Jetronic found in the USA cars.
The mixture adjustment is made by inserting a very long hex wrench into the idle adjusting bore, located under the front inlet tube on the right side of the engine (left as you are facing the engine). The idle mixture is VERY sensitive - a little adjusting makes a big difference - but mostly in the idle mixture.
A couple of things to check first:
Check the resistance on the Temp II sensor, located on the top of the engien near the front. From the sensor pin to ground should be:
-10 deg C - from 7 to 12 kOhms
+20 deg C - from 2 to 3 kOhms
+80 deg C - 250 to 400 Ohms.
These are coolant temps, not air temps.
Check the throttle switches.
The idle switch should be closed at idle, and should open as soon as the throttle opens a tiny bit.
The Wide-Open throttle switch should be open until the throttle is opened most of the way, and should then close.
I would check these things before adjusting the mixture.
"my 85.5 is running way to rich after timing change and maf change.can this be adjusted/whats wrong with it."
I don't really know what an "85.5" is, but the timing on a USA 32-valve '85 engine isn't adjustable. This almost certainly means that Angelo has a 16-valve RoW car with K-Jetronic, not the LH-Jetronic found in the USA cars.
The mixture adjustment is made by inserting a very long hex wrench into the idle adjusting bore, located under the front inlet tube on the right side of the engine (left as you are facing the engine). The idle mixture is VERY sensitive - a little adjusting makes a big difference - but mostly in the idle mixture.
A couple of things to check first:
Check the resistance on the Temp II sensor, located on the top of the engien near the front. From the sensor pin to ground should be:
-10 deg C - from 7 to 12 kOhms
+20 deg C - from 2 to 3 kOhms
+80 deg C - 250 to 400 Ohms.
These are coolant temps, not air temps.
Check the throttle switches.
The idle switch should be closed at idle, and should open as soon as the throttle opens a tiny bit.
The Wide-Open throttle switch should be open until the throttle is opened most of the way, and should then close.
I would check these things before adjusting the mixture.
12-08-2002, 07:19 PM
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I worked on an old 528e one time which had a running rich problem. Everything checked out as fine...
As it turned out, there was a wiring problem between the head temperature sensor and the Motronic unit. It was thinking the engine was stone cold, dumping in tons of fuel.
This car had been in to the shop I worked at several times before...took me 4 hours to find the problem. Connected one wire to ground and it ran like a champ.
It is probably something very simple, so check all your sensors and the like before you start throwing parts at it.
As it turned out, there was a wiring problem between the head temperature sensor and the Motronic unit. It was thinking the engine was stone cold, dumping in tons of fuel.
This car had been in to the shop I worked at several times before...took me 4 hours to find the problem. Connected one wire to ground and it ran like a champ.
It is probably something very simple, so check all your sensors and the like before you start throwing parts at it.
