engine troubles in vitara

[gqmudder91]

hey guys my 1995 vitara jlx efi 1.6 is have engine troubles on idle it goes up and down from 200 to 1200 with out me touching it and when im driving it does the same just like the engine dies then it kicks back like it revs out then drops again it is im possibile to drive on road cant stsy at one speed what is wrong

[zookster666]

It sounds to me like a fuel delivery problem check your fuel pump Is keeping pressure or not cutting in and out

[joeblow]

three letters.......TPS.

[lay80n]

three letters.......TPS.

+1 have had the same problem before on a friends vitara.

Layto....

[gqmudder91]

thanks guys have replaced fuel pump filter and injecters a couple of ppl have told me tps but it is bloody expensive is there any cheaper ways

[PCRman]

Just try adjusting it first, all thats needed is a basic multimeter. The method in the haynes manual is one of the few things that are correct (or close enough to work). If you can't get hold of it I or someone else can post it up.

[gqmudder91]

ok can u tell me how to cant find 1 anywhere

[PCRman]

I'm at work at the moment but it write it up as soon as I get home unless someone beats me to it.

You will need a multimeter, feeler guages (0.08mm and 0.05mm i think) and a stubby philips head screwdriver.

[greg]

i'm no vitara guru, but this sounds similar to an issue i have witnessed on a baleno motored sierra.. the problem turned out to be MAP sensor due to a split rubber vaccum hose on the engine.

it could be worth checking out your hoses first if you are trying to watch your wallet.

the other suggestion is to get your diagnostics tool (a piece of wire) and switch the diagnostics switch so your check engine light can flash out the ecm error codes for you. that would be a much better way of diagnosing the error - or at least getting a good ball park idea of what is wrong.

cheers

[gqmudder91]

yer the bush mechanics way of checking it it came up with code 21 and so ruff guess was the tps so found couple from wreckers with same pins and did not change it

[PCRman]

All of this is done with the ignition off and testing the pins on the component not the pins on the plug that part of the harness.

If you unplug your fitted TPS it should have 4 pins. Name them A B C and D from bottom to top.

1)
Then using a multimeter the resistance between pins A and D should be 3.5 to 6.5 k ohms.

2)
Next check between pins A and C. With the throttle closed the resistance should be between 0.3 and 2 k ohms. With the throttle wide open is should be 2 to 6.5 k ohms.

3)
lastly (this is the fiddley part) put a 0.5mm feeler gauge between the throttle lever and stop screw (its on the throttle body. the screw should have some yellow or white crap on it). The resistance across pins A and B should be 0 to 500 ohms. Now change up to a 0.8mm feeler and check across pins A and B again now it should be open circuit (should read as 1 on most multimeters).

4)
If the measured values are out of these ranges then you need to try adjusting the TPS. Make a match mark were the TPS currently is (lets you out it back in the same spot if you have to). Now loosen the screw on the TPS so that you can rotate the TPS bot only with firm pressure. Put the 0.8mm feeler gauge back in between the throttle and the stop screw and hook up the multimeter between pins A and B. Now rotate the TPS slowly until the multimeter just reads and open circuit (or hoops between open and very high resistance). Now redo 1 to 3 and see if they are in range.


Repeat step four as many time has you need to to either get it in range or decide its .

The distilled version of all this would be

Pins on TPS are A to D bottom to top

Pin Pair resistance
A and D 3.5 to 3 k ohms
A and C (idle) 0.3 to 2 k ohms
A and C (WOT) 2 to 6.5 k ohms

A and B (0.5mm off idle) 0 to 500 ohms
A and B (0.8mm off idle) open circuit


I dont know if a dodgy IAC valve could case problems but if you unplug it and check the resistance between the two pins you should get between 11 and 14 ohms.

If anyone want to make any corrections feel free, I am working from haynes here.

[gqmudder91]

thanks mate will try that next week thank u will let u no how it goes