Tuesday, April 04, 2006 - 08:27 am, by: Eldin Didic(Dvine)
This is a bit of a weird one and I’ll try my best to describe the problem in hope that somebody will understand what I mean and can help me diagnose the problem.
It started about two months ago. My car would randomly lose power when in second gear. Let’s think power delivery on this one. When you have your foot down on the throttle, the car accelerates and the revs (generally speaking) increases. But see the problem I am experiencing is when I am accelerating, first gear has power delivery which is perfectly fine, let’s say 100% delivery. Things seem to change when in second. The car stays at anywhere between 2000 to 2300 rpm no matter how planted the pedal is. The car seems to stay in this hideous state for about 5 seconds before the rpm jumps to about 3500-4000 and power delivery them seems fine again. This problem mainly seems to occur after the car has idled at a set of lights. Does it when kicks back occasionally. So power delivery in second gear at that time seems to be only around the 10% mark if that.
If I want a power take off I mash the thing to the firewall. Car revs fine in first gear, all is sweet, it hits about 70km before if throws itself into second. This is when the problem begins.
Now, I am assuming it has something to do with the fuel filter. I could be wrong and way off the mark on this one. I don’t think it would be the leads because the car does seem to idle and start fine. But again, the car does seem a little rough when idling. Not as smooth as it used to be. But that could just be because of the entire exhaust replacement.
Now, a totally different question... Should I only be using genuine Toyota fuel and oil filters? Will after market ones affect the car in any way? Reduce power so to speak?
If anybody is unclear with this problem, please let me know what you are unclear of and I will do my best to re-describe the problem.
Tuesday, April 04, 2006 - 08:55 am, by: Tim Appleton(Timbo)
It sounds to me as though it would be a thermostat related issue if it happens after typically sitting idle at a set of lights. I think I may have a similar issue.
Has this occurred as a result of the entire exhaust replacement? A new exhaust will change the tuning of your engine, thus power delivery will change, most likely more power towards the top-end of the rev range, and less down low. It will probably change the idle as well.
If the fuel filter were a problem then I would imagine that this would cause a problem over the entire rev range, and at idle. I'm sure there's someone a bit more informed on this one out there.
Tuesday, April 04, 2006 - 09:46 am, by: Mark Paddick(Sparks)
It could be a filter type problem but if so it's a weird one. Once a filter blocks up it usually stays blocked until you back off completely or even stop for a while. It also could be ECU related, the ECU backs off timing on gearchanges and it could be that there's a problem there. Many drivers don't even notice the ECU doing this as it happens only at large throttle openings and is over very quickly....normally. It could also be TPS problems; there is a procedure to check the TPS setup somewhere around here. I would start by swapping ECUs with a known good one (I have a good one here if you're coming at Easter). I wouldn't think the brand of filter would matter too much especially the fuel filter. Toyota oil filters are known to be better than most aftermarket but that shouldn't be a problem either if changed regularly. Changing the fuel filter would be a good idea too, they're cheap and at 15 years it's probably time for one anyway.
Tuesday, April 04, 2006 - 09:58 am, by: Eldin Didic(Dvine)
Mark,
I will start by having both filters replaced anyhows.. So I can rule that out of the equation.
I also thought about the ECU being the problem. But I didn't think a exhaust replacement would affect the car's ecu. Could it be that the car is not getting enough fuel? Maybe time for a unichip?
If all fails, I will come down for a drive and have you fix and change a few little things for me.
Tuesday, April 04, 2006 - 03:03 pm, by: Michael Laysico(Dark_soarer)
I have the exact same problem, except it seems to last longer than 5 seconds in the 2000 - 2300 rpm...all signs pointed to the cats, but got them replaced and the problem still occurs. As suggested by Mark, it might be the solenoids so will be taking it to the mechanic tomorrow and getting it checked out.
Wednesday, April 05, 2006 - 12:45 am, by: Mark Paddick(Sparks)
That's what I think could be the case. Gearbox solenoid problems could maybe cause it but you'd expect to get an ECT flashing light if that was the case unless the ECU was faulty..... Since this seems to have started with an exhaust replacement maybe it is related to oxygen sensor(s). If one or both were faulty then the closed loop ignition/fuelling would be wrong leading to all sorts of weird things as the open loop values are calculated from the closed loop ones and the retarded on gearchange by a fixed amount and then.....who knows what could happen?
Wednesday, April 05, 2006 - 06:51 am, by: Matthew Sharpe(Madmatt)
Hmm, my boss just had a similar problem with his Falcon - turns out it just needed a transmission flush. Same basic symptoms - fine in 1st, then as soon as it hit second nothing for ages like it was stalling up. Same deal if he kicked down from 3rd to 2nd. After the flush he says its now better than it ever was.
Wednesday, April 05, 2006 - 07:48 am, by: Peter Scott(Planetsoarercom)
These symptoms happened to my V8. It turned out to be a faulty solenoid in the transmission. It would change to third or overdrive? instead of 2nd and made the car feel very very slow. New solenoid and just like new. A common problem apparently.
Wednesday, April 05, 2006 - 10:29 am, by: Tim Pike(Keydecoder)
I had a similar problem recently with my V8 when in overdrive and giving a bit of gas up a hill in 2nd it would shudder and lose power. A transmission flush seems to have fixed it though, so it might be an idea to try.