Key linked to ECU 1998 UK Rev 5 N/A

[wilkie senior]

Hi
Key linked to ECU 1998 UK Rev 5 N/A

As above ive never heard of this

Im going through suggested solutions to sort this erratic idle & over fuelling

Talking to someone today about the issue (buying a part) they asked about the key have i linked it to the ECU, I even tried a ECU from a rev 5 breaker to eliminate th eoriginal.

Now Ive never heard of this before (hat means nothing though) its runs as the previous ECU did

now this comment thrown into the pit, im getting pretty hacked of, its on the edge (despite a fortune on bodywork) ditching the thing!!!

I really need to get to someone that can bottom this, but i dont know of anyone near me (skipton / Colne) as the MOT has run out, vicious circle, cant cure this it wont pass mot on emissions, so cant drive it to someone etc etc

(a vert dejected) Brian

[SonicSW20]

The key is NOT linked to the engine ECU. I have swapped out UK market Rev4 and Rev5 ECU's (both use the same security system pretty much) - you can swap them for another of the same part number with no issues. As far as I am aware, its the TVSS box that handles all the key related stuff.

Are there any codes present, and what have you done so far to try to fix this?

[wilkie senior]

Hi there

Thanks for that I thought i was going crazy!!

to my shame no i have not....but tonight we will and take it from there.

Be ready for a long thread ! I hope not!

Regards Brian

[SonicSW20]

Hi there

Thanks for that I thought i was going crazy!!

to my shame no i have not....but tonight we will and take it from there.

Be ready for a long thread ! I hope not!

Regards Brian

Just got to work through methodically, more often than not these things end up being something actually quite simple, its just a matter of going through and testing. Could be as simple as a perished / split vacuum hose somewhere!

[wilkie senior]

Cheers

Ive been going at it all wrong i think I replaced so many things, replaced some vac hoses but there are some i cannot fathom how you get to the other end, they descend into the abyss of the engine bay!!!

I will report back with the results

Thanks for taking the time to reply most appreciated

regards Brian

[Ryan S]

get the car on ramps Bri, It's much easier to work out where stuff goes when you can see from the top and bottom. Looking into the top yields very little in my experience.

[wilkie senior]

With my lack of time & facilities I may be taking it somewhere

Did the fault chaeck last night got 4 flashes then 1,

acording to info Fault 41 TPS Position Sensor
Open or short circuit in throttle signal (VTA)

* Throttle position sensor circuit
*Throttle Position Sensor
* ECU

I already changed the ECU with no change so taking a relative guess that it wasn't ECU ?

We tried setting up the TPS according to BGB, it was hard to get a reasonable result that appeared stable,

Now IDIOT here!!! was messing with the throttle stop screw when it all started, ( I know now you don't mess with this)....or do you?

Now to start the set up process, how to a get the stop to a starting position?

do i adjust the stop so it just touch's? then i can start again

Also on another thread there reference to the switching of "IDL Switch" forgive my ignorance but where what when so to speak

Cheers

[SonicSW20]

IDL is one of the pins on the TPS.

I've never touched the throttle stop screw personally, you should never need to, it's set from the factory and thats it. Is there anything in the workshop manual for it?

If you were able to calibrate the TPS you would have checked that the IDL output on the TPS was working correctly. So, that suggests your TPS is OK. I'd still try another one to be sure, but if it calibrated correctly I think you probably have a wiring issue.

[wilkie senior]

Hi

Yep big homer Simpsons moment re the throttle stop, kicking myself


I will have a look in the BGB to see if theres anything.


i think physical check of the wiring is in order old cars various garages of varying quality of work etc

Thanks chaps all appreciated

regards Brian

[Ryan S]

is the TPS the same on NA and turbo?

[SonicSW20]

is the TPS the same on NA and turbo?

Yeah, super common part. Same on loads of Toyotas from the era. Should not be an issue to find one!

http://japan-parts.eu/?parttt=&part=894 ... i=&cars=ok

[abovetherim]

Here is something to check that won't cost you anything...

Both the TPS and the MAP sensor (thingy near the diag box on the firewall with a vac hose running to the underside) use E2 connection to the ECU. I believe there is a splice in the loom somehere under the inlet manifold.

You could attach a straight crimp connector to some wire then slot this on the terminal (Brown wire IIRC) for the tps plug and run the wire to the boot. Then using a meter check the continuity between E2 pin in the grey plug at the ecu (you can open up the ecu to check which pin as they are labelled but i believe it is on the 16 pin plug) and the tps.
Also do this for the MAP sensor as if this is getting intermittant or broken E2 connection then the engine will overfuel.

Once you have the idle screww set reset the TPS adjustment as per the bgb. and then check with 0.5mm feeler and 0.7mm feeler. 0.5mm should show between IDL and E2 (botton 2 terminals in the connector) 2.3KOhms or less
0.7mm should show infinity.

To set initially it is easier with an old fshioned needle meter. Using 0.6mm feeler in the throttle stop loosen tps screws and move the tps until the guage flicks from infinity to continutity...ish. then check with 0.5 and 0.7

Hope this helps

[abovetherim]

Also worth wipping of the throttle body and the iac and giving them a clean. they can get gunked up.
After cleaning the iac with carb cleaner and checking the gate turns super free dry it out and spray a little WD40 at the bearings (either end of the gate as it were).

[wilkie senior]

Hi I did the throttle body ac while back

But!!!!!! But!!!! Think we found the culprit today

Will post details next time, but seems better

Brian

[wilkie senior]

well sorted it

the fault, well err umm it was well, err


the breather (blue) the little white pipe going into it, got pushed too far, touching the top of the breather housing!!

so pulling it off in a real hissy fit causing it to run, well di i feel a complete as Del boy would say "Rodney, you plonker! "

Needless to say the little b*****r will be made fixed in the appropiate position!!!




oh well just fine tune the TPS setting etc, well at least shes had a lot of good quality parts fitted, plus I have a alot of good quality parts for sale!! ha ah

Regards Brian

"Winner of Plonker of the month award July 2019"

[SonicSW20]

Is that a breather, or is that the air supply for the IACV?

[wilkie senior]

Hi

Its a breather was put there by a previous owner,( i have renewed the filter & check for being clean, on a regular basis)

I have though of plumbing it back in as std? in the induction pipe thoughts?

Brian

[SonicSW20]

If its the one that goes to the intake pipe, thats the air feed for the IACV. Certainly explains the poor idle if it was blocked.

[wilkie senior]

Yeah indeed

I feel such a total "Helmet" ha ha

Anyway at least she can get her ready for a MOT, and crack on with the legal action against the previous body shop for their bodge work that has been corrected now

The Rebirth of the Cosmos Eagle continues

[wilkie senior]

Here is something to check that won't cost you anything...

Both the TPS and the MAP sensor (thingy near the diag box on the firewall with a vac hose running to the underside) use E2 connection to the ECU. I believe there is a splice in the loom somehere under the inlet manifold.

You could attach a straight crimp connector to some wire then slot this on the terminal (Brown wire IIRC) for the tps plug and run the wire to the boot. Then using a meter check the continuity between E2 pin in the grey plug at the ecu (you can open up the ecu to check which pin as they are labelled but i believe it is on the 16 pin plug) and the tps.
Also do this for the MAP sensor as if this is getting intermittant or broken E2 connection then the engine will overfuel.

Once you have the idle screww set reset the TPS adjustment as per the bgb. and then check with 0.5mm feeler and 0.7mm feeler. 0.5mm should show between IDL and E2 (botton 2 terminals in the connector) 2.3KOhms or less
0.7mm should show infinity.

To set initially it is easier with an old fshioned needle meter. Using 0.6mm feeler in the throttle stop loosen tps screws and move the tps until the guage flicks from infinity to continutity...ish. then check with 0.5 and 0.7

Hope this helps

Cheers for that Ill bear it in mind, i did have to read it 3 times ha ha, life was so much esier with my cross flows, twin cams & A series engines, even doing a 1360 with split webers seemed easy compared to these things ha ha