86 audi 5000 CS TQ - idle not controlled
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AudiWorld Member
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I think I would focus on coolant temp sensor and O2 sensor.
Try unplugging O2 sensor and see what idle does when warm.
O2 sensors can start being sluggish as they get old. Poor mileage also supports a bad O2 sensor or possibly temp sensor.
Bentley is calling, my man, Bentley! Need to do the tests for O2 and temp sensors.
Try unplugging O2 sensor and see what idle does when warm.
O2 sensors can start being sluggish as they get old. Poor mileage also supports a bad O2 sensor or possibly temp sensor.
Bentley is calling, my man, Bentley! Need to do the tests for O2 and temp sensors.
Checked codes when running. 2111
Unplugged the sensor: no change in RPM
Seems like an o2. Is there a test on the O2 itself (ohm meter, voltage, etc..)
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Less than 300 miles on $65 of gas. Pretty bad
Looks like a voltage test on the O2 sensor is needed to determine if it works correctly...
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Joined: Feb 2007
Posts: 262
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From: Claremont, CA
Look at the threads in this post carefully, sounds like some of this might apply to your car (this guy was running very rich as well):
http://www.motorgeek.com/viewtopic.p...8103&view=next
halfway down or so someone mentions:
2111 (Blink Fault Code), VAG1551/2 Fault Code Number 00513 RPM sensor Open or short circuit, Defective sensor & cables, metal fragments on flywheel teeth.
O2 sensor (heated 3-wire) has 2 electrical conections (+ and -) for heater, and one for the voltage signal to ECU which has a boot on it that connects to green wire or similar wire to ECU. Measure voltage at O2 output wire and ground (leave heated 2-prong connector connected). It should be around 0.2v - 0.8v and flucuating around 0.5v. A voltage reading that remains low (close to 0.2 v) is lean mixture or high (close to 0.8) is rich mixture.
http://www.motorgeek.com/viewtopic.p...8103&view=next
halfway down or so someone mentions:
2111 (Blink Fault Code), VAG1551/2 Fault Code Number 00513 RPM sensor Open or short circuit, Defective sensor & cables, metal fragments on flywheel teeth.
O2 sensor (heated 3-wire) has 2 electrical conections (+ and -) for heater, and one for the voltage signal to ECU which has a boot on it that connects to green wire or similar wire to ECU. Measure voltage at O2 output wire and ground (leave heated 2-prong connector connected). It should be around 0.2v - 0.8v and flucuating around 0.5v. A voltage reading that remains low (close to 0.2 v) is lean mixture or high (close to 0.8) is rich mixture.
Thread Starter
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BTW: 10 valve engine.
Checked o2 voltage.
When idling it is less than .1v, and only rises toward rich when the throttle is goosed and idles down.
I changed a vacuum hose on the bottom of the ISV and cleaned the ISV with TB cleaner. Worked great for 20 miles, then started fluttering again for 20 miles, OK for 10 miles, then flutters rapidly, etc. There is nothing consistent with this problem.
When the idle is fluttering, if I pull the plug for the ISV and or the 02, there is no change in the flutter. If I pull the plug near the throttle actuator on the intake, the idle rapidly rises.
Checked both temp sensors (single wire on front of head, near the MFTS and both OHM out well. No issues that I see with them.
Pull the oil cap and car dies; Pull the dip stick and it runs like garbage.
Ill look over the site carefully and see what I can find....
Checked o2 voltage.
When idling it is less than .1v, and only rises toward rich when the throttle is goosed and idles down.
I changed a vacuum hose on the bottom of the ISV and cleaned the ISV with TB cleaner. Worked great for 20 miles, then started fluttering again for 20 miles, OK for 10 miles, then flutters rapidly, etc. There is nothing consistent with this problem.
When the idle is fluttering, if I pull the plug for the ISV and or the 02, there is no change in the flutter. If I pull the plug near the throttle actuator on the intake, the idle rapidly rises.
Checked both temp sensors (single wire on front of head, near the MFTS and both OHM out well. No issues that I see with them.
Pull the oil cap and car dies; Pull the dip stick and it runs like garbage.
Ill look over the site carefully and see what I can find....
AudiWorld Member
Joined: Feb 2007
Posts: 262
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From: Claremont, CA
Do you have the test harness (VW 1315, about $30 or make one) to read accuator current, measured in milli-amps, at Differential Pressure Regulator (DPR)? It puts an ammeter (most volt-ohm meters are this too) in series with the DPR electrical connections. You start engine and read the milli-amps, typical readings are +10mA.
This will tell you where air/fuel mixture is at, and what ECU is telling DPR to do about it. This is like the pulse of the system with respect to air-fuel, and O2, coolant temp, throttle microswitches, RPM, etc are inputs.
More info (applies to all CIS-E, aka KE-Jetronic)
http://www.humanspeakers.com/audi/timing2.htm
This will tell you where air/fuel mixture is at, and what ECU is telling DPR to do about it. This is like the pulse of the system with respect to air-fuel, and O2, coolant temp, throttle microswitches, RPM, etc are inputs.
More info (applies to all CIS-E, aka KE-Jetronic)
http://www.humanspeakers.com/audi/timing2.htm
Last edited by socalclimber; Jan 7, 2011 at 03:36 PM. Reason: edit URL for DPR harness
Thread Starter
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Do you have the test harness (VW 1315, about $30 or make one) to read accuator current, measured in milli-amps, at Differential Pressure Regulator (DPR)? It puts an ammeter (most volt-ohm meters are this too) in series with the DPR electrical connections. You start engine and read the milli-amps, typical readings are +10mA.
This will tell you where air/fuel mixture is at, and what ECU is telling DPR to do about it. This is like the pulse of the system with respect to air-fuel, and O2, coolant temp, throttle microswitches, RPM, etc are inputs.
More info (applies to all CIS-E VW and Audi)
http://www.oneilcastro.com/A2Bentley/FU01/ch6.1.6.html
This will tell you where air/fuel mixture is at, and what ECU is telling DPR to do about it. This is like the pulse of the system with respect to air-fuel, and O2, coolant temp, throttle microswitches, RPM, etc are inputs.
More info (applies to all CIS-E VW and Audi)
http://www.oneilcastro.com/A2Bentley/FU01/ch6.1.6.html
Sure don't! Not sure how to get it either...
The Audi just treated me to a busted radiator neck on the upper side! New radiator is on its way, so this issue will resume next weekend once I get it running again.
AudiWorld Member
Joined: Feb 2007
Posts: 262
Likes: 3
From: Claremont, CA
Here's a place that sells the VW 1315A/1 test harness:
http://www.techtonicstuning.com/main...roducts_id=710
http://www.techtonicstuning.com/main...roducts_id=710
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From: Zinzinnati, Ohio
I believe if o2 sensor is not cycling on its own, then its bad. Heater element may be fried. Should change sensor every 60k miles, so if you haven't changed it, you're due anyway. I don't think you can properly adjust the fuel/air without a working o2 sensor.
Audi o2 sensor has high $$ markup....but uses the same o2 sensor as a 1988 Ford Thunderbird. Part # 13942. Is a 3-wire heated sensor, and only diff is that connector is not the same, so you have to splice wires together. I did this using plastic heat shrink connectors. Cost about $30 bucks at rockauto.com, or napa, compared to $100+ bucks at the dealer.
Should also check the top hose to your ISV. It may have a small slit in it, and the slit opens up more as the car gets hot and the hose expands.
Can also take some heavy plastic, place over the top hose connection of the ISV, and push it in the hose and clamp it tight (or use locking needle nose pliers over the top hose to close it off). If idle settles down, then your ISV is bad.
* Try to get an All-Metal radiator if you can. Doesn't cost much more, and you won't run into the broken neck issue again 3 yrs from now.
Audi o2 sensor has high $$ markup....but uses the same o2 sensor as a 1988 Ford Thunderbird. Part # 13942. Is a 3-wire heated sensor, and only diff is that connector is not the same, so you have to splice wires together. I did this using plastic heat shrink connectors. Cost about $30 bucks at rockauto.com, or napa, compared to $100+ bucks at the dealer.
Should also check the top hose to your ISV. It may have a small slit in it, and the slit opens up more as the car gets hot and the hose expands.
Can also take some heavy plastic, place over the top hose connection of the ISV, and push it in the hose and clamp it tight (or use locking needle nose pliers over the top hose to close it off). If idle settles down, then your ISV is bad.
* Try to get an All-Metal radiator if you can. Doesn't cost much more, and you won't run into the broken neck issue again 3 yrs from now.
AudiWorld Member
Joined: Feb 2007
Posts: 262
Likes: 3
From: Claremont, CA
No, air-fuel mixture values can only be read at DPR with ammeter in milli-amp mode using VW 1315 A/1 test harness (as far as I know) or make your own (I can show you mine..it uses 1 male 2-prong connector from heated O2 sensor, and 1 female 2-prong connector from just about any FI connector on the Audi (like cold start valve, DPR, etc.).
You've got half of the harness if you replace the heated O2 sensor! Audi_marv makes a good point about the 60k replacement interval, it's probably a good idea. It is the primary sensor to ECU that controls air-fuel mixture.
I like to use genuine Bosch for O2 sensors, and AutoHausAZ has yours for a reasonable amount, $69 free s/h:
http://www.autohausaz.com/search/pro...xygen%20Sensor
You've got half of the harness if you replace the heated O2 sensor! Audi_marv makes a good point about the 60k replacement interval, it's probably a good idea. It is the primary sensor to ECU that controls air-fuel mixture.
I like to use genuine Bosch for O2 sensors, and AutoHausAZ has yours for a reasonable amount, $69 free s/h:
http://www.autohausaz.com/search/pro...xygen%20Sensor