Mazda Rotary Club

General => General Technical => Anything Engine/Performance/Tuning related => Topic started by: RXSpeedy on September 09, 2009, 08:27:40 PM

Title: Probably yet another PFC thread.
Post by: RXSpeedy on September 09, 2009, 08:27:40 PM
Installed my PFC+commander tonight and carried out the self learn idle tests, the car idles fine when stationary but as soon as i either rev/turn on the lights the car goes hunting? Is it me being stupid or is this quite common with everyone? im only running a filter and exhaust so nothing drastic has been done to the engine. I\'m posting here now for idea\'s so i can resume tomorrow in the light.
Title: hunting
Post by: Eddie on September 09, 2009, 10:23:54 PM
Mine did this as well, the only fix was to unplug the Idle control valve on the back of the plenum, and she idled without hunting at all, as soon as i plugged the control valve back in she would hunt like mad.

Even had her to WGT and pip said leave it unplugged as he could not find out why.

the valve is a black cindlirical type thing near the fire wall attached to the plenum.

had her running without the valve for over a year now and no problem.
Title: Probably yet another PFC thread.
Post by: SiH on September 10, 2009, 08:10:10 AM
Try taking off the ICV and the inlet mani and clean out the air ways - Mine idled a bit funny, and it was due to a combination of oil in the inlet (from weeping tub seals) and the water injection creating a big goop of emulsified oil, which pooled around the ICV and gunked it all up.

A good rinse out solved the issue :)
Title: hunting
Post by: Eddie on September 10, 2009, 08:49:03 AM
Did the idle always hunt even before the pfc? if so then yes a good clen should solve it, but mine was fine before the pfc then went bad after installing the pfc, gave the icv a good clean myslef and tested it and was well within spec but still no joy, from memory was something to do with mechanical idel control and the PFC, sort of goes like this, pfc set idle, mechanical no do it this way, no pfc set idle, and they conflict somehow.


not sure how or why but pip at wgt could not solve it so must abe a tricky little gremlin, klet us know if the clean solves your problem mate.


regards
Title: Probably yet another PFC thread.
Post by: Nik da Greek on September 10, 2009, 08:53:51 AM
Mine did it all the time when the PFC was first fitted, and sometimes a bit of tweaking the idle screw and stuff would stop it for a bit, but eventually it did it less and less and now it hardly ever does it, only very rarely goes back to its bad old random ways to remind me its an RX-7 lol. No idea what caused it or how it cured itself though, sorry :o
Title: Probably yet another PFC thread.
Post by: RXSpeedy on September 10, 2009, 10:35:34 AM
Idle before I installed the PFC was fine no problems what so ever, I did think that the 2 were conflicting somehow but can\'t really understand why they would. Anyways im going to reintialize once more and if the faults still there i\'ll look at the IACV route. Thanks for everyones help i\'ll let you know how i get on.
Title: Probably yet another PFC thread.
Post by: RXSpeedy on September 10, 2009, 12:06:59 PM
Off to a great start, started again this morning and now the speedo was going up and down lol i can only laugh about it because now i can\'t start the bloody thing, tried reverting back to the stock ecu and nothing. Got all the plugs out and tbh if its flooded im a dutchman theres hardly any fuel on them and it doesnt smell anyways going to put a bit of oil in and see what happens, looks like a engine tune is in store so might just take it to a garage lol
Title: Probably yet another PFC thread.
Post by: RXSpeedy on September 10, 2009, 08:25:12 PM
Well a productive day came at 19:30 after a day of removing plugs checking relays checking wiring with a multimeter it all came down to a blown fuse which was stopping fuel from being injected, replaced the fuse started her up as soon as i turned the key so happy days. Only downside is im back to the factory ECU as im not happy with the idle hunting so im going to get a few more bits before i take it in for a map.
Title: hunting
Post by: Eddie on September 10, 2009, 09:39:02 PM
Glad you got it started, thats the problem when you get tinkering lol, things go wrong easy on these beasts.
good thinking on the bits front, I did front mount, de cat, fpr, zaust, rad, rats nest, then the pfc and got a map.

its going back now for hks down pipe, new zaust, fuel pump, new plenum with extra injectors, boost controller.

its best to hold of till you got all your bits not like me paying for 2 mapping sessions :(
Title: Probably yet another PFC thread.
Post by: MaLicE on September 11, 2009, 06:16:29 PM
i get this too and it does my head in!!

which is the ICV?? is it the plug on the throttle body next to the firewall or the plug on the upper inlet mani slightly forward of the other plug?

if i unplug the one on the tb it still hunts and wont rev over 3k... if i unplug the other one it idles really bad at like 200rpm lol...
Title: Probably yet another PFC thread.
Post by: Sidzrx on September 11, 2009, 07:21:05 PM
it\'s on the plenum, white plug
Title: Probably yet another PFC thread.
Post by: RXSpeedy on September 11, 2009, 07:25:47 PM
The smaller of the 2 connectors which ^^ has been said its a white connector. I removed the connector when i had the PFC on and it dropped to around 800rpm.
Title: idle control
Post by: Eddie on September 11, 2009, 10:39:31 PM
Once the iCV valve has been unplugged you need to manualy adjust the bleed idle screw on the throttle and also check the commander for the idle rpm setting,
Title: Probably yet another PFC thread.
Post by: MaLicE on September 12, 2009, 05:02:02 PM
Quote from: Eddie;640857Once the iCV valve has been unplugged you need to manualy adjust the bleed idle screw on the throttle and also check the commander for the idle rpm setting,

thats the screw under the elbow right???
Title: screw
Post by: Eddie on September 12, 2009, 09:47:32 PM
yes the one under the elbow near the throttle
Title: Probably yet another PFC thread.
Post by: Jim_rx7 on September 13, 2009, 07:33:42 PM
Mine done the same if the ICV was plugged in. With it unplugged the car idled fine. Only thing is to start it with the ICV unplugged I have to blip the throttle.

With it plugged in it starts without the blip, but it will hunt.