High Idle with slight misfire

[twoqu]

Lou,
I thought I would post the various resistances you should see:
With throttle closed:
Between terminals 1 & 2 1500-2600 ohms
Between terminals 2 & 3 750-1300 ohms.
Then open the throttle and the resistance should increase to a max of 3600 ohms between 2 & 3.

[220bhp]

Back again,I have been away working, earning the money to hopefully fix this troublesome car,I fitted a new batterie in the multimeter and it seems to work,I tested the TPS and these are the readings

Between terminal one and two 2.292 ohms
between terminal two and three 1.062 ohms
when throttel is open 3.6
between four and six the reading is OL open and closed

I dont know if this makes any sence but I am begining to tink that the TPS may be at falt for some if not all of the problems; not sure about the red hot turbo issue though.
I am beging to wounder if its somthing to do with the new disstributor I fitted , maybe wrong I did double check, but I am no exspert. I realy do appreciate everybodys help in trying to solve my problems and now I am back and with your help will hopefully get to the bottom of it; and then the beers are deffinatly on me Many thanks LOU

[twoqu]

Lou,

If you cannot get the closed circuit (0 ohms) when the throttle is shut, you won't get the idle stabilisation. To simulate this condition, just pull the rubber boot of the connector back and use a piece of wire as a jumper between 4 and 6. Effectively you are bypassing the TPS. That should fool the ecu into thinking the throttle is shut and activate the idle stabilization. If the car then idles properly, you know the tps is dead on that function. The rest of the measurements appear to be within the specs.
Usually if you cannot hear a definate click when the throttle is shut then its dead. Assuming no adjustment has been made to the throttle cable! Just make sure the throttle is against the stop.
Hopefully that might be responsible for your idle problem at least.

[porkkis]

Internal resitance may vary. It's the output voltage you're interested in!
It uses "voltage division" (hard to explain, probably wrong terminology too, someone explain if you can) so don't care about the resistance. Just measure the output terminal that should be near to 0V when throttle closed and near to 5V when wide open. Say 0.2 and 4.8 or so.

[220bhp]

I managed to get someone to help me recheck the electrical items again especialy the TPS and this is what he found between terminals 1/2 a correct reading 2/3 correct 2/3 open 3500, but between 4and 6 it was open circuit open and closed.so am I right in thinking that its not working. We checked the fuses and found that s26 Lamda heater had blown ,so replaced it Also checked the resistance and voltage on the ISV the N75 and the carbon canister valve and all are correct Took the car up the road and its still the same,missfire at 1350revs exsactly,it still heats up very kwickly and seems to be running in limpmode,the turbo was'nt glowing like the last time but it was still running a couple of marks over 90 and the fan came on when we got back, no more than 2miles at an easy pace.I am now going to drain and fluss the,rad take out the thermosate [a new one ] just to be sure I fitted it the right way round and see what happens

[AndyP]

If it is getting that hot in under 2 miles you have a faulty temp sender or there is something seriously wrong with your cooling system.
Have you tried checking to see if the rads are hot all over? or do the have cool spots,indicating that they are blocked.

[220bhp]

I flussed both rads, and they seem to run quite freely and the water is very clean I did'nt refill with g12 incase I need to do it again,
With regard to the running issues. I tried to check the distributor allignment again this time using a mirror and it was out by a millimeter or so.I realligned it and got my son to use his younger eyes.and we both agree that it is now spot on. As twoq suggested I ran a wire from terminal 4to6 on the TPS and the car began to idel properly,I then took the car for a spin, it runs better than its run before,but the missfire is still there at dead on 1350revs the tempreture runs a 95/100 then the fan brings it down to just over 90. Pulled up in my driveway and it was making a gronning noise, like the sound you get from some powerstearing pumps, opened the bonnet and the turbo and EM where glowing red hot again, worrying.So I gess its a new TPS £149 unless some one knows where I can get a secondhand one anyway I am so greatful for all your help ,don't know what I would do without it. And like I said when it is running right at last the beers are deffinatly on me [if I have any money left that is]

[twoqu]

Lou!
Well some progress at least. You will need to do some research. Look for a Bosch distributor in your area, that is someone who sells Bosch parts. Get the Bosch part number of the tps and get a quote. Should be a lot cheaper than that. Failing that try Vagparts.
Having mastered the multimeter, you can know learn the blink codes. Swot up the technique on Paul N's site. Its going to be useful to clear the codes and see what comes up now. Or wait until you replace the TPS. If you have access to a laptop then perhaps its time to cough up for something like vagcom, especially as you have two vehicles it can be used on. You will soon recover the outlay and its a very useful diagnostic tool.
I would think its either running very lean or retarded or both. Did you replace the knock sensor that was flagged up previously as faulty? Go back and check the fuse for the lambda again.

[twoqu]

Oh!
Bridging terminals 4 & 6 to get the idle is only a temporary way of verifying that the TPS is dead and that the rest of the system functions, which it does! Obviously the TPS should be open circuit on those terminals when being used. Not sure what effect it has if you drive around with it connected!
Perhaps someone can comment on whether the ecu remains in limp home unless the fault codes are cleared. Whould have thought that the non functioning lambda would have thrown a mixture adaption code or something!
Even with the previous codes for the ISV, Carbon and Boost solenoid, the ecu should have been in limp home according to both Paul's site and some Motronic info I have!

Oh yank the fuses under the red "motor" cover in the fuse box. I think its 27 for the ecu power. Leave it for a few mins, this should clear whatever faults are stored and start the mixture adaption again assuming that the lambda is now functioning!
Obviously it would be handy to know what faults come back. I know this is getting a bit fussy, but it is a process of elimination!

[twoqu]

Ok, These are the relevant p/n for the 3B TPS.
Audi: 034 133 154F
Bosch: 0 280 120 410

The ABY is different.
Audi: 078 133 154
Bosch: 0 280 120 431.

I am not sure what the difference is or whether it can be substituted.

[220bhp]

Thanks for that Robin ,and yes it is deffinatly progress ,Iam going to replace the tps and I think the lamda as well, I have never replaced it, I thought I had,but when I checked the receipt it was the s6 that was replaced. Checked the receipts for the s2 [some 20 grands worth]but nothing about alamda so I gess its not before time.
Many thanks Lou.

[AndyP]

If you can find a Bosch dealer they are "only" about £95, I bought one recently. If your struggleing, let me know and I'll order one from where I got mine.

Andy

[220bhp]

Cheers Andy I might hold you to that

[220bhp]

Well I changed the lamda tonight, tried the car ,not far, and not very fast, but when I got back home,still the turbo and em are glowing red hot.I can't beleave I am the only one thats ever had this problem someone must have suffered the same symptom, and fixed it, if so i would be very happy two hear from you,in fact I would be more than happy to hear from anyone who has any ideas co;s i'm running out.
I have bought a throttle body containing a TPS from a forum member and am waiting for it to arrive,hopefuly it will solve my misfire and idel problems, but this red turbo issue is very worrying,and I can't use the car until I find the reason,so help us out guys

[DJones]

Are you sure the turbo has not seized up!! heat is generally developed where there is a restriction. if the turbo has seized the turbine rotor will cause a restriction.

Only a thought!