Automatic not shifting beyond 3rd or 4th and revs dropping faster than normal

Ken

Ken

Ken

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Joined
28 Apr 2004
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:confused:

I've recently had the shift solenoid C changed on my IS250 as it was exhibiting 2 main issues...

1. The car won't shift past 3rd or 4th. Sometimes it's 3rd and other days it will be 4th.

2. If I let go of the accelerator say at 70mph the revs will drop rapidly to just above 1200 ish and by that time the car would be at say 60mph. To accelerate I have wait for the revs to rise again for a few thousand revs before the car accelerates. I have to do this gently otherwise the car jolts forward as the engine speed isn't matching the gearbox.

So I came out of the dealership £500 down about a week ago thinking the shift solenoid change that originally brought up a p0761 iirc had fixed the issue. So 10 mins into my journey home I saw the engine light, VSC and traction light has come on again and I was stuck in 3rd gear again.

Turned around and went back to the dealership and they've agreed to refund me the £500. We've agreed that I will be provided a courtesy car from this Saturday to Wed and they will see what they can do. They will put the old solenoid back in, refund me £500 and during those 5 days hopefully resolve the problem including changing the transmission fluid.

Before then though I've noticed the two faults above have been intermittent as I've managed 3 days without any faults though the revs do appear a tad lower than normal as when I let go of the accelerator I still see rev drop though not as severe. About a few hundred rpms. Reading Lexus forums, there have been mentions that drivers have resolved their VSC, engine and traction lights by reconnecting the vacuum line on the intake as it can come loose, changing oxygen sensors and making sure the fuel cap is tight. The latter is how I managed to resolve the problem for 3 days. The oxygen sensors I'm not capable of doing of course and everything seems ok intake/vacuum line wise.

So after 3 days I've got the 2 problems again so this Saturday will be sending the car in. Worse case I've been told 2nd hand replacement transmission will be 2200+labour+vat as Lexus will not take the existing one apart. Reading online I just don't think it's the gearbox.

Quite gutting this. 7 years old and about 105000 miles. It's probably worth 5K if it was faultless and it be madness to change the gearbox!

Any advice appreciated on how I should handle this with the dealership or independently?

Many thanks :)
 
get first, second and third opinions on cause of fault. By that I mean opinions of garages not internet message boards ;)

If gearbox, have it sent away to be looked at... to an independent auto box specialist.. Repair if repairable, replace with second hand if not.
 
Fuzz said:
get first, second and third opinions on cause of fault. By that I mean opinions of garages not internet message boards ;)

If gearbox, have it sent away to be looked at... to an independent auto box specialist.. Repair if repairable, replace with second hand if not.
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Will do. Was hoping Lexus would fix it first time considering they probably have dealt with the fault for other customers too.

Just some threads I've been looking at but will definitely seek independent opinions...

http://www.justanswer.com/lexus/7bimk-lexus-is250-2006-lexus-250-automatic-stuck-3rd-gear.html
http://www.clublexus.com/forums/gs-third-generation/182672-check-engine-light-check-vsc-4.html
http://www.fixya.com/cars/t9666990-06_250_vsc

pepsilol said:
Whats your current fault code?

Sounds a bit valve body blockage to me.
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When I turned around back to the garage the same fault code came up indicating solenoid c fault on the technician's computer. I don't know where the valve body is but the dealership said they will flush through the transmission so hopefully that will clear the blockage.
 
Which Lexus is this? Shouldn't be flushing transmissions.

Valve body is just above the tranny pan after the filter. Controls all your shifting, pressures etc etc.
 
IS250. I'm going to check the fuel cap again tomorrow to see if there's any signs that a tight seal is not being made. The fault disappeared for 3 days after I had filled up and given the fuel cap a good amount of torque.
 
I meant dealer.

The fuel cap tightness is just a coincidence, you have something a bit more serious that tightening a fuel cap.

Sounds like a blockage that comes and goes or a duff sensor.

I assume the solenoid they changed was in the VB?

So they would have put fresh fluid in the transmission when re-filling?
 
mejinks said:
ZF Transmission perchance?
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Nope, it will be Aisin, probably A650E or close to that.

The problem is if it is the tranny then with the dealer its that they have the diagnostics but not the understanding on the live data about the tranny.

With the Tranny specialists, they don't usually have the correct diagnostics but have the understanding about live data.
 
pepsilol said:
I meant dealer.

The fuel cap tightness is just a coincidence, you have something a bit more serious that tightening a fuel cap.

Sounds like a blockage that comes and goes or a duff sensor.

I assume the solenoid they changed was in the VB?

So they would have put fresh fluid in the transmission when re-filling?
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Sorry :o Lexus Bolton.

I'll have to ask this Saturday about whether or not the solenoid they changed is in the valve body. Definitely going to get a few independent opinions on this from auto transmission specialists because quite clearly I don't have a clue and don't want a misdiagnosis or be ripped off.

Thanks so far guys. :)
 
Update:

Lexus changed the Shift Solenoid Valve S3 in the valve body for OBDII code P0761.

The car is now with a auto gearbox specialist and he has tested the sensors and the individual solenoids and he has advised its a fault with the gearbox itself. He has quoted £1800+vat to take it out and rebuild it with a kit. What you think guys? It's cheaper than the £2200+labour+vat for a refurbished gearbox Lexus quoted me but worth it on car with 108000 miles about 7 years old? Everything else about the car is fine to this date, paint is still in very good condition so I'm very reluctant to sell. especially when the car is only worth 5K if the gearbox was working properly. :confused:
 
Tesla said:
Seems a no brainier to repair it.

What sort of warranty do each of your options provide?
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It's one year with the Lexus and the independent I'll ask him tomorrow. What would you expect in return financially if we assume worse case i.e he rebuilds the gearbox and it still doesn't work?
 
Have you looked around for cost of replacement gearboxes from a salvage company?
You may well be able to buy and pay to fit a box you have sourced and have change from that which you have been quoted already.

On the flip side, the gearbox specialist should, at the stage of stripping it down, be able to tell if something has failed and therefore ease your mind somewhat that a fault has been found and it is very likely to be fixed once rebuilt.
 
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Fuzz said:
Have you looked around for cost of replacement gearboxes from a salvage company?
You may well be able to buy and pay to fit a box you have sourced and have change from that which you have been quoted already.

On the flip side, the gearbox specialist should, at the stage of stripping it down, be able to tell if something has failed and therefore ease your mind somewhat that a fault has been found and it is very likely to be fixed once rebuilt.
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Touch wood on that last point! :) Did consider the salvage option but think I've decided to proceed with the rebuild because would rather eliminate the problem on the existing gearbox rather have a salvaged one only for that to potentially have the same problem later. The stuck gear fault does seem to be a common fault judging from Lexus forums.

Anything I need before I give the go ahead besides a written and signed quote detailing work and guarantee?
 
Well so would I to be fair but if you're skint then it at least gets you to work to earn the pennies to do it properly.. ;)
 
I feel your pain.

If it helps you any, I just paid £1600+vat for a rebuild of my ZF 5HP24A gearbox including removal/refitting and a 12 month/12,000 mile warranty (which can be extended to 2 years/24,000 miles for £99+vat).

Unfortunately the place I am using is in Southampton which is quite some way from you up in Bolton :(
 
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