Car back from mechanic

[ChitownMillenia]

got my hose but it is going to thunderstorm today and i dont have a garage so I will have to wait so my work isnt interrupted.

First code combo came back today: P1540 & P0170 but this time with a CE. boy this engine is finicky...

[ChitownMillenia]

I changed out all the vacuum lines today and checked the routing as well, everything is in order. not that hard of a job but you must be very patient and meticulous. took about 5 hrs.

after a day of driving codes came back P0170 & P1540. what should i check next??

[Saint_]

I changed out all the vacuum lines today and checked the routing as well, everything is in order. not that hard of a job but you must be very patient and meticulous. took about 5 hrs.

after a day of driving codes came back P0170 & P1540. what should i check next??[/b]

Get a multimeter and check the solenoids. I think they have two terminals. The resistance should be less than 40 ohm. Not sure if they are all the same. FSM should have some data..

[ChitownMillenia]

I have already changed out the abv vac/vent and one of the egr solenoids a couple months ago. they had different codes and slightly different symptoms. I will still check, it is easy enough but I dont think thats it.

[ken inn]

imho, this has GOT to be a vacuum problem. generally, you never get only 1 side with fuel trim malfunction. it is always both sides, because they are connected. i still think it is a leak where both the abv and right side lines are interconnected. it is also possible that one of the one way valves is on backwards. there are teeny arrows to show which way to flow. the solenoids are operating, otherwise it would throw a 1525/26. so, it must be after the solenoids. just looking at the schematic, check your oneway valves. they are like opposite, not same way. perhaps one is wrong. heck, you can get a simple hand vacuum pump, and test it. http://www.mityvac.com/pages/hvpo_MV8500.htm it would take a while, but sounds like the yahoos that worked on the car dont have the smarts or the incentive to do a good job.

[millyowner]

Uhg, I have learned my lesson with cheap mechanics. I now have a shop where the cost of labor per hour is the highest I've paid, but I know it won't be my problem if I get the car back and something is wrong with it.

An unlikely hypothesis is the valve cover gasket came loose and was pinched or the blind plug was not seated correctly during reinstallation, causing a boost/vacuum leak, which the computer recognizes as a boost control problem, and the metered air imbalance results in the fuel trim malfunction code for the rear bank.

[ChitownMillenia]

I agree with Ken that its got to be a vacuum problem abv related. the one code that is constant is the P1540.

the one way valves are correctly installed. I checked routing of abv lines again and didnt find any issues. I did not however replace the two larger diameter hoses connected to the abv. could that be it?

[ken inn]

I agree with Ken that its got to be a vacuum problem abv related. the one code that is constant is the P1540.

the one way valves are correctly installed. I checked routing of abv lines again and didnt find any issues. I did not however replace the two larger diameter hoses connected to the abv. could that be it?[/b]

those 2 larger hoses share a common chamber in the abv. actually, all but 2 hoses all seem to share the same chamber. the abv is just like a wastegate. pressure builds in one chamber, when the set pressure is reached, the valve opens, and excess pressure is bled off. however, it is a bit more complicated, because this is air that has already been metered. if you look at the color coded vacuum diagram, the very darkest blue line goes from the vacuum solenoid to the diaphragm on the top of the abv. probably the vacuum holds the valve shut, and when it reaches max boost, the ecu tells the solenoid to open. this stops the vacuum to the abv, and the valve opens. there are 2 other small vacuum lines coming off the bottom of the abv, one comes straight down(green), the other at an angle(yellow-green). what about the one way valve on the yellow/grn line, if it is bad, then it looks like it gets vacuum when it shouldnt. just guessing here, i would go out and fool with the intake(i have a spare) but it's really hot. looks like if you put a constant vacuum on the dark blue line, you will then have unlimited boost. if you could do that, and then go for a test drive, but if you mash it for more than just a second, it might blow the motor. however, if no code comes back, then that is the circuit. someone somewhere might have info on what each solenoid does, normal open, normal close, and when they pop. otherwise, i say it's a simple leak, like a bad tee/vacuum line, but you say you changed them all.