dheck

iTrader: (9)

I need some serious help guys. I took a 1000 mile trip to florida in my car and now it wont start at all. It was acting funny when I arrived. It was sputtering around 3K and then it finally died. It has a very hard time idling and most of the time it dies. I am throwing a P0108 code MAP high voltage circuit. I checked for vacum leaks and could not find any. My LTFT's are between 5 and 8% at an idle. My MAP is at 30in with the key in the on position. Now the car wont start at all. If I pump the gas it will fire and run as long as I keep giving it gas but it runs very rough and as soon as I let off it dies. I need help, I am stranded and have no way home.

VoodooWS6

Sounds like a sensor that is telling the computer that there is no air (just fuel). Check your MAS sensor and see what the voltage range is. I had this problem before on other F-bodys.

dheck

iTrader: (9)

MAS? do you mean MAF or MAP? I am going to try and replace the MAP sensor and see if that fixes anything.

VoodooWS6

Mass air flow sensor. I guess people refer to them in diffrent ways. Does this help?

Also check your coolent temp sensor.

dheck

iTrader: (9)

Just out of curiosity, why the coolant temp sensor. It seems to be operating correctly. I ordered another MAP sensor and I am going to see what that does for me. I am running out of ideas.

VoodooWS6

Well, the coolent tempature has little to do with actual coolent temp believe it or not (in this example). Sometimes when they go bad, the fuel injectors dump more fuel into the cylinders than needed. That casues a read from the ECU to tell the timing, spark and air ratios to adjust poorly, thus causing the car not to run. Just an idea. After thinking about your code and your issue, it probably does not pertain to you. Hope this helps.

Alex

dheck

iTrader: (9)

Well, I replaced the MAP sensor and no change. The same code is pending. Here is what I came up with on my A-Tap

In park at an Idle I have:

22 deg timing
IAT - 79 deg's
LTFT 1 - 10.2
LTFT 2 - -1.6
MAP 76 in Hg
MAS 1.5 lb/min

My O2's are all over the place

The car will barely idle and sputters all through the RPM range. It is idling at 600 RPM when it usually idles at 900 or so. I dont have a fuel pressure gauge but there is fuel in the fuel rail. MY LTFT bank 1 would sometimes spike to 25 making me think I have a vacum leak but it could have been a A-Tap glitch. IT stayed at 25 and never moved. Then I restarted A-Tap and it never went back. They are between 8 and 9% in drive. I am stumped. What should I do?

hourang

iTrader: (6)

unplug the maf sensor and see if anything changes?

dheck

iTrader: (9)

Well I figured out the problem. I had a broken valve spring. I would assume this is where the increased PSI came from due to the valve not opening. This is what was setting off the MAP code. I can not get new patriot springs here so I am replacing the one that broke with a stock retainer and 918 and hope that it gets me home. Patriot is sending me a whole new set of springs and seals free of charge NO questionas asked, so I guess it's not that bad. The rocker was digging into the retainer due to the larger diamater and it caused the valve to break. The inner spring was still holding the valve up luckly. Now I just have to hope that I don't break another one on the way home. Thanks for the help.

ws6outlaw

Sorry to comment on this old thread but I had the same issue and this is one of the first google results so hoping this might help someone else in the future. Mine turned out to be a bad MAF sensor that probably got wet.