Developed a strange hesitation
12-14-2020, 09:56 AM
#16
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Location: San Diego, Ca, USA
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Re: Developed a strange hesitation
I don't have nitrous or a place to mount the pod so I'll have to pass. Thanks
12-21-2020, 01:00 PM
#17
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Re: Developed a strange hesitation
I went back to the tuner who did my original tune and he wasn't able to connect with the computer either. Apparently I have some wire tracing to do to find out why. I'll let you know what I find.
12-25-2020, 11:14 AM
#18
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Location: Post Falls, Idaho
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Re: Developed a strange hesitation
I think most code readers have trouble with our cars. I actually use my computer and a plug I bought on Ebay. Interested to see if you got a fuel pressure gauge and what the results were.
12-29-2020, 10:43 AM
#19
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Re: Developed a strange hesitation
Christmas decorations are getting put away this week so I will be able to get to the car again. I found an old mechanical oil pressure gauge and I'll use that as a temporary check for the fuel pressure while driving. Hopefully, I can eliminate that as a cause.
08-24-2021, 02:53 PM
#20
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Re: Developed a strange hesitation
Been quite a while but finally got the issue solved. I have tried everything I could think of: new plugs, clean the injectors, clean the MAF sensor, tested the TPS. I finally had the tune shop connect it to their computer on the dyno (what they used originally to tune the car) and he said it was showing wiring issues with the driver's side O2 sensor that was causing it to go out of closed loop and go lean causing the hesitation. He also said that there was a switched 12v wiring issue with one or more of the injectors.
I checked the continuity of all the wires from the O2's to the computer and they were all good. I also checked for switched 12v and ground for the heater circuit in the O2's - both good. I checked for switched 12v at each injector as well as connections to the computer and everything was fine. I found a test for O2 sensors on YouTube and checked both O2's by heating the tip with a propane torch and checking the output voltage. Both went up to almost one volt and back to zero when I took the heat away indicating that they were working properly (according to the test procedure). The O2's didn't test bad and they had less than 2000 miles on them but I replaced them anyway with new Delco (genuine GM) units. Took it out this morning and it ran like the good old days. So much for the YouTube test.
I'm still going to get the car run on the Dyno and see if the new exhaust makes more than the 469 rwhp and 479 rwtq that the old single 3" did. Stay tuned (no pun intended)
I checked the continuity of all the wires from the O2's to the computer and they were all good. I also checked for switched 12v and ground for the heater circuit in the O2's - both good. I checked for switched 12v at each injector as well as connections to the computer and everything was fine. I found a test for O2 sensors on YouTube and checked both O2's by heating the tip with a propane torch and checking the output voltage. Both went up to almost one volt and back to zero when I took the heat away indicating that they were working properly (according to the test procedure). The O2's didn't test bad and they had less than 2000 miles on them but I replaced them anyway with new Delco (genuine GM) units. Took it out this morning and it ran like the good old days. So much for the YouTube test.
I'm still going to get the car run on the Dyno and see if the new exhaust makes more than the 469 rwhp and 479 rwtq that the old single 3" did. Stay tuned (no pun intended)
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