Mazda Rotary Club

General => General Technical => Anything Engine/Performance/Tuning related => Topic started by: saxon on August 18, 2005, 07:56:49 PM

Title: pfc probs?
Post by: saxon on August 18, 2005, 07:56:49 PM
Hi guys, i have just fitted a new pfc and commander and the install went ok. When i accelerate in the car my red heat light flashes on and off very quickly. i have searched for this problem and all i could find was someone else had it, but when they were off the gas, not while accelerating. other than that the car seems ok. Could someone please tell me whats wrong and if the car is ok to drive? As ive just, this last half an hour, fitted it i obviously havent had the chance to get it mapped yet but that is coming, money permitting! Also watching the knock sensor on the commander every time i accelerate it races to the end of the scale? Not good me thinks....Thanks in advance for any help!
Title: pfc probs?
Post by: asp on August 18, 2005, 08:08:21 PM
i think the heat light cums on wen theres 2 much engine knock,
best not to boot it till some 1 else tells u different,
i mite be wrong thou,wait till some 1 esle posts a reply,
Title: pfc probs?
Post by: saxon on August 18, 2005, 08:09:23 PM
Thanks for the quick reply
Title: pfc probs?
Post by: maximtaylor on August 18, 2005, 08:09:54 PM
Don\'t boot it!

It could be just a dodgy knock sensor, or it could be worse. Get it checked out at your local rotary garage for peace of mind.

Things it could be include:

knock sensor mullered
plugs
leads
coil packs
timing out for some reason
fuel pump
overboosting
etc
etc
Title: pfc probs?
Post by: Mart160plus on August 18, 2005, 08:22:38 PM
What was the PFC like when it mapped itself Saxon ? It was me who was getting the quick double-flash of my sensor, did it again last night on the way home after a ding-dong with a GT-Four, yet again only when letting of the accelerator or when I touch the pedal every so slightly.
Being at the same stage of mapping as you I\'m quite interested. My PFC made my engine hunt for hundreds of miles, it took ages (and woke the neighbours!!). What level of modding do you have ?

Mart.
Title: pfc probs?
Post by: saxon on August 18, 2005, 08:54:40 PM
hi, my car has full open exhaust, greddy double air filters nothing else as yet performance related. my car doesnt hunt too much at all, just worrying me as my light comes on with the throttle and yours doesnt seem to, so i think i have a more serious problem than you maybe?
Title: pfc probs?
Post by: asp on August 18, 2005, 10:24:48 PM
there u go,best take max\'s advise n get it looked @ :)
Title: pfc probs?
Post by: Mart160plus on August 18, 2005, 10:43:34 PM
Although I have mid pipe and back box I have standard air box with a K&N filter and my inlet temperatures range from 50 down to 38. Yours are probably up nearer 80+ and so knock would be more possible. Best get it mapped.

Good luck, let us know how you get on.

Mart.
Title: pfc probs?
Post by: rxangus on August 19, 2005, 07:57:24 AM
Yes this light is confusing. It can come on for a variety of reasons but depending on the flash rate, it can mean different things. It\'s difficult to accurately assess whether it\'s flashing twice or four times a second when you\'re at Mach 2!

What I can say is that Pip mapped my car and the 1) settings in the boost screen were set to 0.80 primary and 0.80 secondary with 56% and 66% duty respectively. These are what  I normally use.

I\'ve been playing with the secondary settings as I have been seeing low (0.6bar) boost after the transition. At the moment my secondary setting is 0.85 72% and this is much more responsive. Only thing is that I occassionally get the PFC warning lamp on the dash. I\'ve been monitoring knock and injector duty very carefully and they\'re okay so can only assume the light relates to actual boost exceeding the set point by >0.25bar (from memory this is a warning level) but then again neither of my boost readouts would indicate this.

I would suggest getting it professionally checked or lowering boost and duty and seeing if the lamp warning disappears. Any changes are at your own risk though!!

Angus
Title: pfc probs?
Post by: saxon on August 19, 2005, 08:33:17 AM
Thanks for all the advice think i am gonna have to take it to pips and swallow the bill. Ive had it just over a year and its been totally reliable so i owe it some tlc.