TB MAP Sensor & TB Clean

[Neelskit]

Hi All!

Thanks for your feedback on my "New TB" Post. I ended up getting a 2002 EXT 4X4 with 70k miles. I didn't like the payment for a 2005 LS and this one is an LT rather than a LS. However, I did get a warranty.

Anyway... I read an older post from a few months back that was talking about throttle body cleaning and was also suggested that the MAP sensor be cleaned as well. What type of cleaner do you reccommend for the MAP sensor? So far, I love this truck, but would like a little better mileage than it's been getting. (10-12 MPG city) It just got an alignment courtesy of the dealer and all the maintenance is up to date. It runs very good, but I think it could benefit from a cleaning.

And last question: What are the thermostats set at on the 4.2 L6? Mine seems to be running about 210 F during all conditions. Anybody ever dropped a 180 F thermostat in a 4.2? Would this cause a problem with the PCM?

Thanks!!

[riverajuan]

Hi I have the same truck 2002 Lt 4x4 it looks like 10 to 12 mpg is low it was happening on me I replaced the spark plugs and the air filter those thinks the dealer wond do it unless you paid for seriusly I dont like to take my truck to the dealer I do everything my self I don't like dealers at all unless I have a recall about the temperature 210 Dgs is normal but don't let it go another line over

[fortcarp]

To clean the throttle body just disconnect air intake at throttle body. A good carb/throttle body cleaner readily available at any parts place should surfice. You will need an assistant to work the pedal as you spray it down as these are throttle by wire trucks with no linkage at the throttlebody to advance as the truck tries to die as you spray. MAP sensor, I don't think it is cleanable....however the the air charge sensor between the throttlebody & airbox may benifit from a good cleaning. FYI rockauto.com has most of the various sensors.....along with most other parts, for these thrucks (with pics!!), for those like me that are acyronym challenged. Symptoms of hesitation especially dropping into drive with wheels cut are conducive with this cleaning. Try Chevron Techron gas additive 1st, at least 2 tanks worth. It treats only 12 gallons per bottle. Mine improved some, but did need the TB cleaning. OBTW, I did notice a gain in fuel economy after the full cleaning. You say ALL maintenence has been? Make sure, crawl under there & look at the fuel filter...if it still has the GM hyrogliphics, it has NOT been changed.

[Neelskit]

Thanks for the info...

That was part of the deal with buying the thing- dealer had to complete required maintenence to date. However, I did check to make sure they did.

Right now it's back at the dealer getting new shocks- the rear-end has a sag in it that they were supposed to fix when we bought it. Three trips later, tires balanced, alignment, and new sway bars, they finally put new shocks on it!

[Neelskit]

Got a can of STP throttle body cleaner and went to work. There was quite a bit of carbon build up. Cleaned off the IAT sensor, too. Have noticed a great improvement in performance, but too early to tell on the MPGs.

Thanks for the help!