I have a weird shifting issue with my Pajero/Montero. The transmission in question was supplied by Aisin-Warner to Mitsubishi at the time, until they started using their own transmissions in 2001 on these vehicles. Mileage is currently 336,000 km (210,000 miles) and apart from the issue I'm about to describe, the truck is as smooth as butter. I've always gone the extra mile maintaining and taking care of it.
Simply put, gear changes are delayed, and you have to either slightly release the gas pedal or depress it further (for it to speed up) to shift. As an example, you're doing 80 km/h (50 MPH), and should be in overdrive (4th gear). But you're in 3rd with the RPMs at 3,000 km. If you very slightly take your foot off the gas, the transmission shifts into 4th and the RPMs drop to 2,000. Alternatively, if you put your foot down further, the engine will rev higher as the vehicle accelerates and then you're in 4th gear. The shifts are also a bit hard and sudden, almost like a neutral drop. I don’t know what the cause is, although I was initially leaning towards the TPS.
Worth noting, apart from cooler line flushes, a couple of ARX runs and filter changes, nothing has been done to the transmission and it is all original.
A very knowledgeable person informed me that Mitsubishis of this era depend on the TPS, but also there may be a sensor/magnetic switch on the transmission that detects the shift. A web search reveals this "switch" to be an "Input/Output Pulse Generator":
So I went ahead and had a word with my parts guy at the Mitsubishi dealer, who told me there is something called an "A/T Inhibitor Switch" on my transmission:
So I did another couple of web searches, and it revealed that this is more or less a neutral safety switch. Some people have gone ahead and replaced it because the engine wouldn't crank in park or neutral.
Being ever so confused, I contacted the Service Manager at the dealership, who I'm on friendly terms with, and he said he would get their head tech to take a look at it. He takes the truck for a drive, and comes back to say it's perfectly normal. I've been driving this vehicle for the past 12 years and know straight up this is not normal. My fuel consumption even went up slight since this problem arose. So now I'm even more confused.
I just wanted to ask if someone in the know can tell me whether or not the "Inhibitor Switch" is a modern alternative to the "Input/Output Pulse Generator" and if this would cause the symptoms I'm experiencing. How likely would the chances be of a faulty TPS?
I don't want to play the guessing game, because a new TPS costs $120, whilst a new inhibitor switch costs $165. If I go ahead and replace both of them blindly, or replace one and then jump on the other one as being the "culprit", I'm just wasting time and money.
This is way over my head, as I know next to nothing when it comes to automatic transmissions.
Any input will be very much appreciated!
Simply put, gear changes are delayed, and you have to either slightly release the gas pedal or depress it further (for it to speed up) to shift. As an example, you're doing 80 km/h (50 MPH), and should be in overdrive (4th gear). But you're in 3rd with the RPMs at 3,000 km. If you very slightly take your foot off the gas, the transmission shifts into 4th and the RPMs drop to 2,000. Alternatively, if you put your foot down further, the engine will rev higher as the vehicle accelerates and then you're in 4th gear. The shifts are also a bit hard and sudden, almost like a neutral drop. I don’t know what the cause is, although I was initially leaning towards the TPS.
Worth noting, apart from cooler line flushes, a couple of ARX runs and filter changes, nothing has been done to the transmission and it is all original.
A very knowledgeable person informed me that Mitsubishis of this era depend on the TPS, but also there may be a sensor/magnetic switch on the transmission that detects the shift. A web search reveals this "switch" to be an "Input/Output Pulse Generator":
So I went ahead and had a word with my parts guy at the Mitsubishi dealer, who told me there is something called an "A/T Inhibitor Switch" on my transmission:
So I did another couple of web searches, and it revealed that this is more or less a neutral safety switch. Some people have gone ahead and replaced it because the engine wouldn't crank in park or neutral.
Being ever so confused, I contacted the Service Manager at the dealership, who I'm on friendly terms with, and he said he would get their head tech to take a look at it. He takes the truck for a drive, and comes back to say it's perfectly normal. I've been driving this vehicle for the past 12 years and know straight up this is not normal. My fuel consumption even went up slight since this problem arose. So now I'm even more confused.
I just wanted to ask if someone in the know can tell me whether or not the "Inhibitor Switch" is a modern alternative to the "Input/Output Pulse Generator" and if this would cause the symptoms I'm experiencing. How likely would the chances be of a faulty TPS?
I don't want to play the guessing game, because a new TPS costs $120, whilst a new inhibitor switch costs $165. If I go ahead and replace both of them blindly, or replace one and then jump on the other one as being the "culprit", I'm just wasting time and money.
This is way over my head, as I know next to nothing when it comes to automatic transmissions.