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Randy, Auto Specialist
Category: Car
Satisfied Customers: 9075
Experience:  25 Years Experience Automotive Technology.
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2002 isuzu ascender: Im working..the check engine light..engine codes

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I'm working on a 2002 isuzu ascender, the check engine light was on in the car shut down. we had about a dozen engine codes like p0753 p 0758 p 0740. any help in figuring out how to solve this problem would be helpful thank you.
the engine codes were p o 758 p o 753 p 0740 p 0785 p 01516, then again was p0740 p 0753 p 0758 np 0785

Randy :

I will be glad to help help you figure this out.

Randy :

I have 25 years experience specializing in auto transmissions and detailed technical support.

Randy :

Give me just a moment and I will check on this for you.

Customer: great thanks!
Randy :

I ran a check on those codes and they are all Transmission related, however it is not likely to have that many problems at one time unless there has been a hot to ground problem such as jumping the battery and crossing the cables or something that would send 12 volts into body ground. I can give you some things to check that would cause a multiple DTC set however I from my experience and research on this particular vehicle the one I would check first is the TPS.

Randy :

The code 1516 does lead to Throttle Position Sensor- Mass Air Flow Correlation Error.

Randy :

All the other codes are shift solenoid errors.

Randy :

In my experience I have never seen any of those codes cause a complete engine shut down which leads me to believe that something out of the ordinary has happened. The only way to be sure and certain you find the cause is to do a very thorough in depth test and diagnostic procedure. I will be glad to give you the schematics and test procedures.

Customer: okay any help is appreciated. how can I check the tps
Randy :

Do you have scan tool.

Customer: okay the plot thickens some more information. last week he had complained of the car being hard to turn at low speeds. he discovered that he had been driving inXXXXXfor almost a week and didn' realize it.
Randy :

I can you give you steps to check with a voltmeter, it is a little more difficult.

Customer: I have a scan tool that gives that will give freeze frame data
Randy :

Yes that will be good. The way to check the TPS is in datastream mode. Watch the Throttle Position Sensor while you press the accelerator pedal slowly it should go from 0.5% to 98% gradually. Give me a little more time and I will give you complete diagnostic procedure, it will probably save you time in the long run.

Customer: that would be great I really appreciate your help. we are going to call it quits for today but will be working on it tomorrow as well
Randy :

Great. I will get that posted for you.


It would be great if I could have the complete procedure to print up before I leave home tomorrow. So much easier than trying to read it off my phone. Thanks

Randy :

No problem. Can you print PDF download.

Randy :

If you want to replace TPS, you can do that instead of running these test. There is no gaurantee that it will fix it but sometimes it is cheaper than spending several hours on test. I cant be positive but I think if it were me I would replace TPS and if that did not fix it I would replace PCM.

Customer: thanks so much for all your help I will give it a go today but it does look like the tps . I'll let you know either way thanks again
Customer: Update, It was the TPS. Thanks!!
I am glad to help. If you need anything just let me know.
Randy and 2 other Car Specialists are ready to help you
Customer: replied 4 years ago.
Update- It was the TPS. Thanks!!
Your welcome! Glad to help!

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