B6304 Mass Air Flow Sensor wiring

double_platinum · Post by **double_platinum** » 07 Jan 2009, 07:36

Ok I think I have it figured out. I went back to the RPM sensor and wiggled the wire near the sensor itself, and the car fired right up, after shutting off, I still had a no start, but wiggled the wire again, and it fired up again. Have a spare so I will be installing tonight. Looks like the RPM sensor was installed behind the coolant lines, so the lines were pushing on the base of the wire, which certainly caused the short. Thanks for the help though!

Post by **billofdurham** » 07 Jan 2009, 11:26

So far so good but let us know the final outcome for future reference.

Bill.

double_platinum · Post by **double_platinum** » 08 Jan 2009, 07:57

No luck, still seems to be a timing sensor problem though. A cleared codes, tried starting again, and it came back with a 1-3-1, this is after not only replacing the RPM sensor 2 times, and wiring it directly to the big wiring connection just to rule out any bad wiring. So just to sum up, I have checked all grounds, even the crazy one underneath by the driver side motor mount, though my hand looks like hamburger from it, replaced: both power stages, both coolant sensors, RPM sensor, MAF meter, maf meter ground wire, idle air valve, cleaned the butterfly, new fuel pump relay (even though this was ok, just wanted to rule it out), all the fuses having anything to do with ignition or fuel. Still no spark. Is there any way the flywheel could have demagnetized? I am at a loss, and am just about ready to have it towed to a shop, first time I have had to do this in 10 years. Anybody have any other suggestions before I bite the bullet?

double_platinum · Post by **double_platinum** » 08 Jan 2009, 09:47

Sorry to keep this thread going, but I think I have found the problem. Maybe someone can let me know if I am correct. The wiring from the cam sensor and crank RPM sensor doesnt go to the big 52-54 pin plug under the black cover, does it? It looks as if it goes under the brake booster and then on to the ECU near the throttle pedal (havent gone sub-dash yet to verify). Am I correct in this? If so I am going to try to directly wire it as close as I can to the ECU. I shook this wire this morning and it fired up, no start after shutting it off until I did this again. Anyone had to do this project ever?

Post by **billofdurham** » 08 Jan 2009, 12:27

Sorry to keep this thread going

No apology necessary. We want you to have your car mobile.

Unfortunately, I only have system wiring diagrams for the 960 and they don't show the connector plugs as such. However, what I have is possibly a 36 pin connector which does take all the wires from those two sensors.

Cam sensor: Red to pin 5 then to ECU 8; Blue/black to pin 22 then to the injectors; Green/grey to pin 20 then to ECU 30 having joined the same colour from the throttle position switch and the rear knock sensor.

RPM sensor: Pink to pin 32 then to ECU 47; White/black to pin 33 then to ECU 48.

Bill.

double_platinum · Post by **double_platinum** » 08 Jan 2009, 18:15

OK well here goes again, I took an extra rpm sensor connector and hooked it up as a rpm sensor jumper and wired it in hard to the pink and black/white wires coming out of the ignition control module, next to the ECU under the knee bolster on the driver side. Still no fire. Next jump I am going to try is straight to the ECU. still getting code 1-3-1

DanR · Post by **DanR** » 10 Jan 2009, 08:56

double_platinum wrote:Sorry to keep this thread going, but I think I have found the problem. Maybe someone can let me know if I am correct. The wiring from the cam sensor and crank RPM sensor doesnt go to the big 52-54 pin plug under the black cover, does it? It looks as if it goes under the brake booster and then on to the ECU near the throttle pedal (havent gone sub-dash yet to verify). Am I correct in this? If so I am going to try to directly wire it as close as I can to the ECU. I shook this wire this morning and it fired up, no start after shutting it off until I did this again. Anyone had to do this project ever?

Yes it does go thru the big plug and there can be corrosion that will impede resistance. What a great job that cover does on keeping out humidity and salt spray from the road.

DanR

double_platinum · Post by **double_platinum** » 14 Jan 2009, 07:55

Back again. Got the RPM sensor fed straight to the ECU with good wire (back probing the jumper to the sensor gets normal ohm resistance from the multimeter), still no spark. Cleared the code, if I try to start the for more than 5 seconds it will come back with a 1-3-1 code. Tried test mode 2, and after I activate the starter the computer says it is getting the timing pick up (1-4-1) signal. I am at a total loss here. Am I right to think that either the ECU is junk or the flywheel has somehow become demagnetized? I am not getting a bad ECU code at all.

danr960 · Post by **danr960** » 15 Jan 2009, 15:33

Have you inspected the large 54 pin plug on the driver side front wheel hump?

I remember reading about some poor soul who had a plug where just one pin would slide out of position and avoid making a connection. For him unplugging it and visually inspection was not enough, he spent months in search of a cause before pulling on the back side of the plug and finding a loose wire.

Could it be that simple for you?

DanR

double_platinum · Post by **double_platinum** » 16 Jan 2009, 06:40

I did check the large connector, cleaned it (though all the metal was clean already). All the wire ends were tight as well. I will go ahead and double check it tonight, as I have had the plug moving around a bit due to me fudging with it almost every time I checked or replaced a sensor. Will check in and let you all know what comes of it.

B6304 Mass Air Flow Sensor wiring

Re: B6304 Mass Air Flow Sensor wiring