jack roberts

Hi Red, When my vehicle was having the issue on the M1 and a mechanic was sent out to check, I hoped we would get a result as the fault was in full swing. Alas, he didn't pick anything up! Not sure if he was missing something or didn't check the correct areas, but computer said NO... I am writing to Tech One now and mentioned that my suspicions are a faulty throttle control system (with concerns over catalytic converter and possible manky fuel tank) and will see what they have to say. This conversation has been useful for me to learn what may be at fault, so if they mention anything abstract from that, I'll tread cautiously! Cheers again

Heya Konrad, thanks for the link on that garage, very useful! Yes, I did a lot of troubleshooting and checking out what I could get my hands on in the car, but this conversation thread has been useful in bringing things up I missed/ didn't know about. I'll let the mechanics know what I haven't been able to check on myself so that they can assess the points everyone here has mentioned. Hopefully is cheap indeed, and hopefully I can get this problem sorted!

Cheers Bernard. I've got an MOT due soon so will take my car to a proper Toyota Garage and bring that up too- it was something I considered, just didn't have the means to check myself. Thanks for the advice so far guys!

Heya Notoyboy, I thought the fuel filter could be at fault, but have not had the means to check it myself. Joe, I'm beginning to think the same thing actually- your comment led me to this video and it sounds relative! Particularly how the video says 'the vehicle may be limited to second gear and not go any faster than 35mph.' Sounds like what I've been through! Will have to check for faults on that part using a scan tool. Sounds like a promising lead! Thanks!

Cheers much for that info Joe, mad cyberpunk advice! Will have to try it out. Hiya Red_Corolla, in answer to your question- yes, both things happen; power is lost as though my foot wasn't on the pedal at all. The engine basically returns to idle, even when cruising at speed. The rev counter drops down to match this. When this happens, I've dropped gear to try and remedy quick- but even with pumping the gas pedal, the engine reluctantly returns to running with low power and with low engine revs. Usually dropping down another gear gets the engine revs back- they jump way up the counter and when I ease off acceleration to avoid redlining, power drops quickly and it is hard to find a position on the gas pedal to maintain responsible engine revs. So the issue is the engine power suddenly disappearing from a steady cruise with engine revs being erratic thereafter. The rev counter is only visually showing how the engine struggles, I don't think the rev counter is at fault. This happens on journeys over around 50/ 60 miles. I hope that describes my issue better, thanks for taking the time!

Cheers Joe, Toyota Techstream, first time hearing about this but sounds like a good lead! Have you used the software yourself? Is it set apart from typical car diagnostic programs in that it is specialized for Toyota's? Thanks

I have a Toyota Avensis 2008 estate with manual transmission and it runs on petrol. I bought the car in 2021 with 83471 miles on the clock. I’m based in London and after doing a couple of weekend trips not too far out of London, the car started acting up. First instance was when driving back to London from Folkestone- I was cruising in 5th gear around 70mph when revs were lost on the motorway for a couple of seconds before returning to normal. I thought I had just eased up on the pedal too much, but the closer I got to London with roundabouts and lights forcing me to change gears, revs would completely vanish- despite putting the gas pedal all the way down! Revs would suddenly return aggressively but cut out next to 3000 in second gear and above. It was a pretty stressful drive getting back home- bunny hopping away from lights and revs being erratic; either way high or not there at all. I had no warning lights appear on the dash throughout all of this, which was odd and had me question my driving! I did some research myself and ran through possible issues- Cleaned the MAF sensor (was a little sooty), checked spark plugs (all clean), checked air filter (like new) and topped up the coolant as it was rather low. I took the car to a nearby garage and they ran a computer diagnostic check that brought nothing up. A couple of months later I did a decent road trip- from London to Hampshire and back a couple of days later, a night in London, then on to Cambridge for a night before making the trip up to the lake district. The car had no issues on this journey, so I thought all my tinkering had worked. However, when it came to driving back to London from the lake district in one journey, the issue returned about 2 hours away from London! Revs completely cutting out near 3000 in any gear and struggling to get them back over 2000 from there. Revs were sluggish when/ if they came back- no matter how far down the gas pedal was. I waited on the hard shoulder of the M1 for an hour before the AA requested I get to the closest fuel station. Getting there was a trek with the engine still acting gammy. When the mechanic pitched up he checked the spark plugs- still fine, the air filter and hoses all ok. Throttle body was clean after removing the intake hose and checking the butterfly flap. Coolant levels fine, engine oil fine and battery was good. He even ran a computer diagnostic check that once again brought nothing up and I had no warning lights come on throughout all of this! After weighing up my recovery options, I made the decision to continue the journey and luckily made it back home safe- now well versed with the sound of each car’s horn I encountered on that last stretch… Since then, I have checked the EVAP purge valve and it is ticking away as it should and not leaking in any way. I have also added injector head cleaner to my fuel. I have had the issue return a couple of times since this, albeit not as aggressive. Still no warning lights come on whenever the car is going through this. I plan on taking my car to a proper Toyota garage to get it remedied but would appreciate if anyone has an idea of what might be going on so that I can request that the mechanics zero in on the issue. It would be great if I can sort it out myself and avoid that cost. I don’t believe the issue to be caused by E10 petrol, as it started happening when I was exclusively using E5 and my car has a 3ZZ-FE engine, which is compatible with E10. Hopefully I didn't purchase a lemon! Any relative advice would be appreciated! Cheers much