cipprio Posted April 26, 2015 Report Share Posted April 26, 2015 For months I had some intermittent running problems with my prefacelift 140. The main problem was a dodgy maf so after being replaced the car regained it's response,smoothness and power. It's now about 4 months on since the change and the engine is returning back to it's old ways. I understand that the ecu in the vvti learns your driving style and adjusts to give proper air/fuel mixture. I've now reset the ecu and all is fine again.. this seems very weird to me and is a reset needed every few months or is there a problem somewhere. Most of my driving is short trips a few miles long into work and back..I only get a few miles on a bypass to open her up a little but generally the engine is not to temp so I can't push her to much. I know when the ecu needs a reset as the engine runs rough throughout the rev range. Link to comment Share on other sites More sharing options...
ams Posted April 26, 2015 Report Share Posted April 26, 2015 Is your new Maf any good? Link to comment Share on other sites More sharing options...
cipprio Posted April 26, 2015 Author Report Share Posted April 26, 2015 Yes ams I guess so it's been ok for a few months. Engine started playing up again ie: lumpy and power loss. Just reset and it's fine again..could it be the maf again breaking down. I'll see how long it keeps running ok. I've done the de butterfly mod, could this be a bad thing. Link to comment Share on other sites More sharing options...
VVTI Posted April 26, 2015 Report Share Posted April 26, 2015 I have done the de butterfly mod on my 1999 140 with no bad side affects just more responsive and louder exhaust, so it should be fine on yours. I stay away from supermarket fuel, that might be a factor in lumpiness what do you use, shell is the best but I use my local BP which seems fine. sound Maff sensor again but no expert myself. Link to comment Share on other sites More sharing options...
cipprio Posted April 26, 2015 Author Report Share Posted April 26, 2015 (edited) Just done a 30 mile round trip and all fine with engine..I only use shell fuel after finding out last year how bad supermarket fuel performs in the celica engines. I'll monitor the maf and see how long it is till I get a change in running. I may even just order another maf from ams. I have done the de butterfly mod on my 1999 140 with no bad side affects just more responsive and louder exhaust, so it should be fine on yours. I stay away from supermarket fuel, that might be a factor in lumpiness what do you use, shell is the best but I use my local BP which seems fine. sound Maff sensor again but no expert myself. I love the sound that the debutterfly gives. Along with the new exhaust I hope to get fitted should be sweet. Edited April 26, 2015 by cipprio 2 Link to comment Share on other sites More sharing options...
gen7nnb Posted April 26, 2015 Report Share Posted April 26, 2015 Maf should be ok. It was mine, which came from ams last year or year before and was no problem before. Link to comment Share on other sites More sharing options...
cipprio Posted April 26, 2015 Author Report Share Posted April 26, 2015 Maf should be ok. It was mine, which came from ams last year or year before and was no problem before.thats what i thought Dave, im sure it's working fine as it's been good since we fitted it. Now good again after the reset...weird. Link to comment Share on other sites More sharing options...
madcusslerfan Posted April 28, 2015 Report Share Posted April 28, 2015 Possibly a daft question but how do you reset your ECU, do you pull then reseat the EFI fuse? Link to comment Share on other sites More sharing options...
cipprio Posted April 28, 2015 Author Report Share Posted April 28, 2015 Possibly a daft question but how do you reset your ECU, do you pull then reseat the EFI fuse?I just pull the efi fuse out for 1 minute mark then replace. Mine runs like a dream then, but seems to be returning to running rough a few days after now. Link to comment Share on other sites More sharing options...
Akuma77 Posted April 28, 2015 Report Share Posted April 28, 2015 or undo the battery guys Link to comment Share on other sites More sharing options...
cipprio Posted April 28, 2015 Author Report Share Posted April 28, 2015 or undo the battery guys Yes that as well baz but got fed up of resetting my head unit..lol 1 Link to comment Share on other sites More sharing options...
Akuma77 Posted April 28, 2015 Report Share Posted April 28, 2015 thats how i reset my ecu when i put the blitz panel filter in (i know it relearns anyway ) 1 Link to comment Share on other sites More sharing options...
cipprio Posted April 28, 2015 Author Report Share Posted April 28, 2015 Dont know what the hell is going on with my car but its really starting to get me down, the intermittent running problems is back, yesterday she ran rough and today she ran like a gallon of buttermilk going through a hound dog. What shall i do? I cant see it being the maf as im sure it would run rough all the time if this was shot. Maybe the ecu is on its last legs i dont know. Link to comment Share on other sites More sharing options...
geraintthomas Posted April 28, 2015 Report Share Posted April 28, 2015 Lambda sensor? Possibly? Link to comment Share on other sites More sharing options...
cipprio Posted April 28, 2015 Author Report Share Posted April 28, 2015 Lambda sensor? Possibly? Been thinking lambda since i started having the problems but though i might of got an error code if it was that. Dont know if i can get them tested some how. Link to comment Share on other sites More sharing options...
geraintthomas Posted April 28, 2015 Report Share Posted April 28, 2015 Could always see if ams has one, just to rule it out? But I can see what you're saying about the ECU. If every time you reset it the car appears fine, then I'd also think the same. Really strange that matey. Link to comment Share on other sites More sharing options...
cipprio Posted April 28, 2015 Author Report Share Posted April 28, 2015 If i can get 2 cheap it might be worth just changing them to rule them out..It so intermittent that's the weird thing. Link to comment Share on other sites More sharing options...
slybunda Posted May 4, 2015 Report Share Posted May 4, 2015 Use obd reader too get lambda readings Link to comment Share on other sites More sharing options...
cipprio Posted May 4, 2015 Author Report Share Posted May 4, 2015 Use obd reader too get lambda readingsDidn't realize that would work make. Thanks. Link to comment Share on other sites More sharing options...
gen7nnb Posted May 4, 2015 Report Share Posted May 4, 2015 I don't know if my OBD Bluetooth one will do that. Shame I didn't keep the 1zz ecu from my old engine to test it out. I thought about it but wasn't sure what I would use it for. Link to comment Share on other sites More sharing options...
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