PhillysTahoe
TYF Newbie
This is my first post here hoping to get some input.
I'm going to start from the beginning: at the beginning of December I started looking for a 99-03 Tahoe. In March I finally found one for 5200 bucks bought from the original owner with 137k miles on it and it's loaded! Guy said he only used it to tow his 20 foot camper up north an back in the summer and for family camping trips. The low miles made sense. From the get I noticed that it was getting terrible gas mileage I'm talking 8 mpg consistently. So I took it to a few local shops nobody could figure it out. I took it to Midas one day to have them install a new super 10 flowmaster for me and had them scan just to see if they could figure it out. They found that the number 1&2 coil packs were not bad but read less volts then the rest. So I went to autozone bought two coil packs and threw them on. No change in fuel economy. My truck runs great but it does have a small surge at idle. Has since I've had it. The guy I bought it off of installed a trailer brake and a k&n CIA as well, so I cleaned and recharged the air filter cleaned the maf sensor, cleaned the throttle body and blade and put a new tps sensor on, no change. I gave up. Finally I found this guy on craigslist that does performance tunes and engine diagnostics so I figured I'd give him a call. After 45 minutes of telling him my story he said unplug your maf sensor and see what happens, he said it should hesitate when you unplug and then shut off when you plug it back in. Not my truck! My truck stayed running even after I unplugged it and then plugged it back in. He said something is causing it to be stuck in an open loop. Also my maf sensor is good its not bad. One last note when driving my truck and it's done this since day one, my battery voltage meter on the dash will drop below 9 volts when I let off the gas and then jumps back up above 14 when I get back on the gas. It doesn't do this every time I touch the pedal but it does it enough to be bothersome. My battery tested fine as well as my alternator. Any ideas!!???? Thanks in advance
I'm going to start from the beginning: at the beginning of December I started looking for a 99-03 Tahoe. In March I finally found one for 5200 bucks bought from the original owner with 137k miles on it and it's loaded! Guy said he only used it to tow his 20 foot camper up north an back in the summer and for family camping trips. The low miles made sense. From the get I noticed that it was getting terrible gas mileage I'm talking 8 mpg consistently. So I took it to a few local shops nobody could figure it out. I took it to Midas one day to have them install a new super 10 flowmaster for me and had them scan just to see if they could figure it out. They found that the number 1&2 coil packs were not bad but read less volts then the rest. So I went to autozone bought two coil packs and threw them on. No change in fuel economy. My truck runs great but it does have a small surge at idle. Has since I've had it. The guy I bought it off of installed a trailer brake and a k&n CIA as well, so I cleaned and recharged the air filter cleaned the maf sensor, cleaned the throttle body and blade and put a new tps sensor on, no change. I gave up. Finally I found this guy on craigslist that does performance tunes and engine diagnostics so I figured I'd give him a call. After 45 minutes of telling him my story he said unplug your maf sensor and see what happens, he said it should hesitate when you unplug and then shut off when you plug it back in. Not my truck! My truck stayed running even after I unplugged it and then plugged it back in. He said something is causing it to be stuck in an open loop. Also my maf sensor is good its not bad. One last note when driving my truck and it's done this since day one, my battery voltage meter on the dash will drop below 9 volts when I let off the gas and then jumps back up above 14 when I get back on the gas. It doesn't do this every time I touch the pedal but it does it enough to be bothersome. My battery tested fine as well as my alternator. Any ideas!!???? Thanks in advance
