Throttle Position Sensor

[swampy]

Hi Im new to your forum and im need of some help/advice
I have an 1996 landcruiser 80series 4.5L petrol auto 225,000km
Over the last year I have been getting a reving problem!
I can start the car and it will idle at say 825rpm's hot or cold start.
Then out of the blue I will be sitting at the lights or hot or cold start and it begings
The RPM's goes hay wire it will drop all reves or they will screem out at 2200 rpms ( not good in a auto)
some times I can sit there and watch the taco RPMs gauge go from 700 ish RPMs to 2200 RPMs
This can happen on any given day first start or after 2 hours driving ect.
I have had the car in the shop a few times to differant motor mac's and it wont play up I even let them take it home.
I'm leaning towards the Throttle Position Sensor !!
Any help would be greatly apresated .

 

[swampy]

Any one??

 

[Jon Wildsmith]

The 4.5l petrol isn't as common in the UK so there isn't as much experience here compared to the diesels. A good place to search would be the 80 series section of ih8mud.com . If that doesn't help then yes it sounds like a throttle position sensor or possibly a wiring fault.

 

[Dave Docwra]

No real experience on the petrol version, I would suggest Having a look for some damaged wiring & especially in an area where water can get in i.e near bonnet gaps, I do not think it will be a TPS but could be worth having a look at the Throttle Body (butterfly).

 

[BobMurphy]

Does the petrol thingy have a vacuum-operated 'idle-up' valve attached to the throttle (like that on the diesel) ???

Mighy be something going on there if it does.

Bob.

 

[swampy]

Thanks for the input,
The TPS unit is going in and out as it should.
A couple of months ago I had it of and tested it. It seemed to be working as it should.
So i did the carbie cleaner bit on the butterfly and sorounding area ,this seemed to help out with littel to no problems for a number of weeks, but then returned,
When I had the TPS unit of I noticed there was NO gasket . So I sprayed the area while the motor was running with Airo start, I had no increast in revs, telling me there was no air leaks.
While I was useing the Airo start I gave every vacume hose a hit looking for air leaks and increas in revs.
Tomorow I will give the wireing a hit with water and play with the wires.
I didn't mention the cruiser is also on LPG gas.

 

[swampy]

I found this site for cheap sensors
http://www.shopmos.net/search?q=throttl ... 5336685215

 

[Garry]

Have you looked at the MAF sensor ?

May have some shite on it !

 

[Gav Peter]

Now there you go again Garry, geting us all confused with that techno-jargon...

 

[swampy]

I booked the Cruiser in for an auto service and was told that the oil pressure was to high it had been set for towing also the TPS was on its way out, only working at 1/4 revs.
So now the car changes smooth and when the sensor arrives from the states I will be 100% all good.
I could have brought a sensor here but thet want any thing fron $220 up to $750,
were as I can get genuin from the states and by giving my vin no
I'm garantied to get the rite one. Hopefully and it cost under $50 to the door!!