I have a 2003 MCS, with 51,000miles. upgrades, MTH, 15% pulley, UUC exhaust, Dinan intake.

If you have seen my posts recently, I had an AGS installed then took it off because of vacum problems. to get it back to stock i had to reuse the M7 provided hoses that come off the intake runner. The factory provided hoses were stiff and stronger than the rubbery M7 hoses, this was about 3 months ago.

To this date no problems until yesterday, i was driving about 90mph and all of a sudden the car does what can only be described as "stall" temp gauge goes up, lights come on, then all of a sudden all back to normal, car drives just like it did before. All i could think of that may have caused this would be the use of rubbery hoses that come the intake runner body, cause this to happen?? maybe if they are pinched? WHAT ARE THESE HOSES? I tried to contact classic mini for the parts but they only have 1 hose shown on there.

I know this is a lot to take in, let me know if you guys can help.

 

Anyone?

 

Now when I try to start the car the temp goes all the way up, and it wont start, checked oil, checked coolant, all ok. Any ideas? This is intermittent too, it will be fine, then it will go back to not starting.

 

Something preventing flow to the radiator, perhaps?

 

I'm trying to understand the problem:

1) Is the car going into limp mode?

2) Is it throwing and CEL or SES lights?

3) Since removing the AGS have you had any further symptoms of vacuum loss?

It is possible that during all of the work to install and uninstall the AGS that the engine wiring harness was damaged. I do not think that you have an engine cooling problem - I think that the ECU is reading a fluctuating voltage signal, possibly from either the thermostat or the coolant sensor via a pinched or damaged wire on the harness.

I hate to say this but I would recommend having the dealer perform a scan - this should give you an idea of whether or not the problem is electrical.

The engine wiring harness is a sub $300.00 part and takes the dealer about 4 to 6 hours to install. A lot of 2002 and 2003 have had issues with these.

 

It's my guess that it's an electrical problem, most likely a pinched wire from one of the sensors or an open circuit at some point. Since you say that the car quits and the temp gauge rises, most likely it's a failure of the sensor power circuit that powers the various sensors with 5 volts. If this voltage gets affected, it throws the calibration off on all the sensors that use it (temp, MAP, TMAP, cam and crank position, etc) and puts the ECU in total confusion mode. Some early versions of the AGS came with defective harness extensions which have caused issues with the ECU and the TB plug, so that is worth investigating. You might even have a failing ECU, depending on what codes are thrown at the time. Double check the ECU harness connectors too (remove them and check for bent pins or corrosion and replace).

Good luck!

 

Everyone thanks for all the advice! I poked around the engine and right above the drivers side wheel well there is a ground bolt that looks like it grounds a harness of some kind. the bolt was loose! when i tightened it back down, all systems were GO!!!

i was scared it would be something huge and just after my warranty ran out. so once again thanks guys!

 

Glad to hear it all worked out