1st DataMaster Scan - Need help!
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Joined: Jun 2007
Posts: 52
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From: Germantown WI
1st DataMaster Scan - Need help!
Hi everyone,
I have been looking around these forums for quite a while, but never needed help before.
Car is a 1995 Polo Green 6-spd. No Mods except for muffler eliminators. Car runs like crap
The car is stumbling/hestitating when accelerating. Fuel pressure is 42 and does not leak down. All injectors measured good in the coil test.
Last week, I broke the serpentine belt and replaced.
I have the FSMs, but really do not know where to start, so I did a DataMaster capture and was hoping this would help lead to the problem.
I am a Sunday afternoon mechanic and not very skilled to debugging mechanical problems. My datamaster file is located at:
http://www.freefileupload.net/file.p...42306/ron1.uni
Please take a look at records #460 to #1625.
Thanks in advance for your help!
Ron
I have been looking around these forums for quite a while, but never needed help before.
Car is a 1995 Polo Green 6-spd. No Mods except for muffler eliminators. Car runs like crap
The car is stumbling/hestitating when accelerating. Fuel pressure is 42 and does not leak down. All injectors measured good in the coil test.
Last week, I broke the serpentine belt and replaced.
I have the FSMs, but really do not know where to start, so I did a DataMaster capture and was hoping this would help lead to the problem.
I am a Sunday afternoon mechanic and not very skilled to debugging mechanical problems. My datamaster file is located at:
http://www.freefileupload.net/file.p...42306/ron1.uni
Please take a look at records #460 to #1625.
Thanks in advance for your help!
Ron
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Start by looking at why it thinks the left bank is lean at idle, look at the left header to make sure there is no exhaust leak before the O2, and make sure the AIR system isnt allowing oxygen into the exhaust stream when it shouldnt.
When its off idle, it seems to think the whole thing is lean.
Check for vacuum leaks
Check the injectors are all firing and all are getting a signal to fire
See what it does if you unplug the MAF and then scan it again while its disconnected
Check and clean the throtle body, including the IAC path.
Check the PCV system to make sure its not allowing air in where it shouldnt.
Check the EGR system is shut fully when it should be.
Check the brake booster isnt allowing air in where it shouldnt
Try swapping the primary O2 sensors with each other (put the sensor on the left over on the right, and the right sensor on the left) and see if the issue follows an O2 sensor.
For some reason it thinks its lean on one side and sometimes both, so you need to figure out whether or not it is really lean, or if that is a false reading caused by one of the above. If its a false reading then it will be adding fuel it doesnt need to add.
What does it do when the A/C is not on? Does this make any difference?
When its off idle, it seems to think the whole thing is lean.
Check for vacuum leaks
Check the injectors are all firing and all are getting a signal to fire
See what it does if you unplug the MAF and then scan it again while its disconnected
Check and clean the throtle body, including the IAC path.
Check the PCV system to make sure its not allowing air in where it shouldnt.
Check the EGR system is shut fully when it should be.
Check the brake booster isnt allowing air in where it shouldnt
Try swapping the primary O2 sensors with each other (put the sensor on the left over on the right, and the right sensor on the left) and see if the issue follows an O2 sensor.
For some reason it thinks its lean on one side and sometimes both, so you need to figure out whether or not it is really lean, or if that is a false reading caused by one of the above. If its a false reading then it will be adding fuel it doesnt need to add.
What does it do when the A/C is not on? Does this make any difference?
