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Gary
Gary, Chevy Technician
Category: Chevy
Satisfied Customers: 16212
Experience:  15 years GM master tech
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2004 buick rendevous wont comeplete drive cycle over 120

Customer Question

2004 buick rendevous wont comeplete drive cycle over 120 miles all kinds driving freeway stop and go

Submitted: 1 year ago.
Category: Chevy
Expert:  Gary replied 1 year ago.

I am sorry for the long wait

which drive cycle is not running ? or which monitor is not running ?

Customer: replied 1 year ago.

catalyst, heated o2, an evap

Expert:  Gary replied 1 year ago.

all of those will not run ?

and there are NO codes set in the computer ?

was was the system set to start the drive cycles ?

does the fuel gauge work correctly ?

Customer: replied 1 year ago.

yes cleared codes because of po131 also LT fuel trim -18 and higher all o2s reading WITH IN RANGE HAD UPSTREAM O2 CHANGED 2 MONTHS AGO sorry for the caps

Expert:  Gary replied 1 year ago.

no problem at all

disconnect both battery cables for 5 minutes then touch the 2 battery cables together for 2 minutes then reconnect both battery cables to the battery this will force the engines computer into a full reset and should reset all the monitors and then drive the van they should all run and either pass or fail within 75 miles and also make sure the fuel tank is up @ 3/4 when you start the driving

usually this will get them all to run

with no codes this usually does the trick

Customer: replied 1 year ago.

po131 just came on in 140 miles

Expert:  Gary replied 1 year ago.

ok so now it has a code 131 ?

any access to a scan tool to see live data ?

Customer: replied 1 year ago.

yes

Expert:  Gary replied 1 year ago.

how does it run ?

any vacuum leaks ?

Customer: replied 1 year ago.

only thing i didnt like was long trem fuel was at -18 and higher butter fly was filthy cleaned it that then it ran great

Expert:  Gary replied 1 year ago.

when driving this under the conditions the light triggers what is the O2 MV reading ?

Customer: replied 1 year ago.

0 to .8

Expert:  Gary replied 1 year ago.

lets see if another expert has any ideas

hang on another expert will reply back to you

Customer: replied 1 year ago.
Is the -18 long term fuel trim bad