Wierd Signal / cutting out problem while driving help!

Mini_Alex · Post by **Mini_Alex** » Wed Jun 18, 2008 2:17 pm

Ok got the mj unit running again, and have been out for a drive, just before 2k revs and with a load of 85-100 its almost as if the signal cuts out, with the laptop running it shows that the timing snaps to the lowest bin, i.e. top left, which in my case is 16 deg, and sits at about 1700 revs. Can any1 think what will cause this???!!!
Alex

Post by **brentp** » Thu Jun 19, 2008 6:10 am

On the surface , from your description it seems to be loosing the PIP signal under those conditions.

However, I'm wondering if you might have your TPS wired incorrectly (you're running TPS, correct?) - if it's wired incorrectly you might be shorting TPS +5v VRef to ground when you go 100% throttle.

If you're running TPS- please test the following as an off chance test:

with the engine not running, but the electrics powered up (key to 'run'), go wide open throttle with the accelerator. Does the configuration software loose communication with the unit? look for the "timeout..." message in the status bar.

Let us know what you find out..

Mini_Alex · Post by **Mini_Alex** » Fri Jun 20, 2008 3:08 pm

Ye i thought it might be the pip / saw signal aswel, but i wasnt sure why it would be under those exact conditions! Im actually running map sensor..... so is it likely that its the wiring for the pip signal?

Thanks

Alex

Post by **brentp** » Fri Jun 20, 2008 3:16 pm

Hi Alex,

Yes- if you're running a MAP sensor than it would seem that the source of your problem would point to the PIP signal not being read reliably by the MJLJ. Whatever the MAP sensor is reading really shouldn't affect the fundamental operation of the system- so I think the problem lies in the electrical domain surrounding the PIP signal.

Regards,

Mini_Alex · Post by **Mini_Alex** » Sun Jun 22, 2008 12:25 pm

Thanks brent, ill do a bit of re-wiring.

Alex

Mini_Alex · Post by **Mini_Alex** » Mon Jun 23, 2008 4:57 pm

ok... i have now rewired the pip, saw, power and grn wires from the edis to the megajolt but still it seems as if the signal is cutting out when under load at very low revs, i.e. if i change into fourth when going slow and try to acellerate. Could it be that the edis module is faulty?? as it is now happening with both the megajolt plugged in and unplugged, or could it be a faulty vr sensor??

Alex

Post by **brentp** » Mon Jun 23, 2008 8:29 pm

What RPM range is it exactly? Usually stumbling/cut-out problems occur at mid-rpm range where an insufficiently-rigid sensor brackets might resonate. However, that usually happens independent of engine load.

The EDIS module and VRS sensors are usually extremely robust, but you could still swap them out.

Are you sure it's not problem other than ignition?

Mini_Alex · Post by **Mini_Alex** » Tue Jun 24, 2008 12:14 am

I think i may have solved the problem, and i think it was the VR sensor, as i swapped it out and the car has been fine today! Funny tho as the sensor was new from KAD with their kit!
Neways thanks for all the help

Alex

Post by **brentp** » Tue Jun 24, 2008 12:32 am

Interesting. Is It a Ford OEM sensor, or some other design?

Mini_Alex · Post by **Mini_Alex** » Tue Jun 24, 2008 11:40 pm

im not sure if its oem or not, all i know is that its obviously variable reluctance, but does not look the same as the ones which are usually used or got with the edis kits. Here is a link if ur interested, http://www.kad-uk.com/crank-sensor.htm

Alex

cng1 · Post by **cng1** » Wed Jun 25, 2008 8:06 am

That is a weber-marelli sensor,as fitted to cosworth turbo engines. It's a standard VR sensor but I haven't personally ever tried using one of those with EDIS as the proper EDIS sensors are cheaper and easier to come by.