hi all

My 94 disco started to idle erratacally and was slowly getting worse, also another issue was at about 3500 rpm the power deleivery was a surge of power, i was seriously thinking the dreaded cam lobe had worn off,
i put a vacumm gauge onto the motor and had about 17" vac, we wound the dizzy around to max vac and then retarded it about 1" of vac, i then went for a test drive, more power but still had a surge and also detonation, i drove home thinking about the symptoms, and came up with the MAF being dirty, a ford 302 i have has had the same symptoms, any way got it home, pulled the MAF out and apart, the hot wire had a little bit of crud on it, i sprayed it with brakleen and then blew it out with compressed air and reassembled it, and then put it back in, the change was staggering, the idle is now rock solid, the drive is loads smoother, no surging, runs very very nice now, have had no low idle issues since, starts eaiser, is not as rich when cold.


i had pulled the IAC valve out and cleaned and lubed that but had absoultley no change, i got the plunger out by having the motor idling and unscrewed the IAC valve, as i wound it out the plunger wound in to compensate, eventaully it fell out, getting it back in was KOEO a few times to wind in in.

Cheers Pedronz

 

Thank you very much for this info!!!!!!

 

Would add that working on the hot wire MAF sensor is best done cold, brake parts cleaner cools things off quickly, like putting a hot light bulb filamant in ice water, extreme temp change could kill MAF sensor.

 

Use CRC MAF Cleaner for great results.

 

brakleen works quite well as well, not sure i have seen maf cleaner over here, as for the hot wire I would think unless the ign is on it would be well cool enough to spray, once you get it off the motor and strip it.

cheers

Pedronz