Overfueling now, 944 Turbo - updated Fixed with pics

[diabloam]

http://www.porscheclubgbforum.com/tm.asp?m=527274&mpage=1&key=򀳄

Recent post above of problems with my Turbo. Anyway went offshore and came back 20 days later. When I parked up car before I left I thought it was smoking heavily, but was in rush so thought Id worry about when back.

So went for run on arrival home. Straight away, car pouring smoke out, not blue, looks to be unburnt fuel and it smells like it also, car also stumbling and missing. Car idling low now! Went for a blast and got her warmed up, runs better once warmed but still loadsa smoke when gunning it. Took a spark plug out and its pretty sooty, also the smoke looks sooty and the tail pipe is black.

Anyway thinking car is overfueling a lot at idle and lower revs, could my dodgy tps be causing this or is it something else. I notice I cant hear the microswitch click on starting to move throttle off closed position or click when it goes back closed any more and I am pretty sure it use to. Any suggestions everybody! Thanks in advance

 

[barks944]

My TPS clicks as soon as I move it, so it does seem like yours has a problem. Go onto [link=http://www.clarks-garage.com]www.clarks-garage.com[/link] they have a guide for adjusting the TPS.

 

[ukmastiff]

I know naff all re mechanics and know my problem wont be everyones but mine had a boost leak and also the maf was knackered. I mention it as I had smoke on booting it and had coughing and rough idling also. With its leak fixed and new Maf it runs like a dream now. Just in case it helps Regards Mas

 

[Frenchy]

TPS or MAF no big deal, it will fix, keep us posted.

 

[sulzeruk]

I have a TPS and a MAF from a car you can borrow if you want to check yours out, Alasdair

 

[diabloam]

Going to try and take it off tomorrow and see what it is doing in regards to section in clarkes-garage. Sulzeruk are your tps and maf known to be good functioning ones, thats a really kind offer and appreciate it and may take you up on offer if i dont have any joy looking at it. Have bought 30ft of 5/32 vacuum tubing and some T-pieces so might change them out and see if I can see anything amiss whilst doing that, Has anybody changed this (its not Promaxkit or anything just bought by the metre of ebay) am assuming it should be fairly obvious when I start it. Will post back with how I get on, any other suggestions to try whilst I am at it please let us know, thanks for the help everybody. Its annoying that these running probs are just occuring when I was about to splash out on some tuning (wastegate etc), annoying!

 

[sulzeruk]

Parts are on a running car at the mo so they should be OK, Alasdair

 

[diabloam]

Never got chance to look at car today as was welding up my old range rover for its MOT the morrow. But hopefully it wont fail and I will have garage free to investigate problems with my 944t and give it some tlc its been crying out for, lol. Will post back how I get on when have done so!, cheers

 

[bennyboy]

My TPS clicks as soon as I move it, so it does seem like yours has a problem

Can anybody explain how this sounds? I have an overfuelling problem and can't say that I have heard any clicking near the throttle?

 

[diabloam]

Hey all. Got chance to look at car, went to start it and it was running rough, missing badly and smoking like crazy, could hardly get it to drive up slope to the garage. Anyway got it in and started stripping. Whilst doing so I did notice some oil in the turbo to intercooler pipe. Now I know you always get a misting in there, which mine had but it also had little pool in the low spot of hard pipe section (grooved bit that helps hold the soft pipe jubilee clipped in. Is this ok, turbo is still boosting fine and smoke doesnt appear to be blue, looks more like over fueling and defo smells crazy rich so hope this is still fueling and not blown turbo? Anyway, defo no clicking noise from TPS going onto idle and back off (should click each way, yeah?) so took it off and popped top of it. The sliding contacts look ok and resistance seems to change smoothly al la Clarkes guide test procedure. But it looks to me like the microswitch is jammed in, although given I have never seen inside one of these, I aint sure. Anybody want to look at this pic (in small album below) and tell me its not an inductor type pick up and that wee plunger looking thing on side of TPS (wee round thing on white microswitch inside TPS) that the throttle/TPS Slide contact goes against when returning to idle, it should be sticking out when TPS is turned away from against it but in the photo it doesnt, it looks stuck in, anybody? http://s701.photobucket.com/albums/ww14/diabloam/TPS%20and%20Running%20probs/ But surely this would mean it would be stuck on idle setting and that should just stop it from reving up, rather than the crazy over fueling i think i have, HELP anybody who has had similar problems Sulzeruk, I stay in Scottish Isles so its hard to borrow these from you, although I do appreciate the offer, they would need to be posted up or something, would you be willing to sell them? Or do you or anybody know where would be the best place to get a TPS (and perhaps a AFM) asap, as I want to try enjoy my car whilst I am off at the moment. Sorry for really long post, thanks all!

 

[sulzeruk]

PM me your address and I will get the TPS and AFM in the post to you tomorrow to try, I have a turbo coming in for the chop with good bits on it if needed, Alasdair

 

[diabloam]

Hi, been investigating further, think the TPS is defo knacked but just the microswitch, think the slide contact is ok! Well it changes smoothly with (resistance reading on multimeter) along its whole movement, so would need one of them anyway. Discovered a vacuum line disconnected, one between bottom of throttle body and the "temperature valve" (I think thats what it is?). So made a new hose up and stuck that on. Just put my knacked TPS back on (right PIA to get bottom screw back in) and going to see if that hose makes any difference to how car is running (anybody want to predict the outcome!). Sulzeruk, That great, can I try these parts and buy off you either or both (Am defo needing the TPS as idle microswitch is kaput I reckon 99%), I appreciate your trust and promise not to abuse it. Away back out to carry on putting it back together, hope I have made some progress. Thanks all

 

[diabloam]

well threw it together with new vacuum pipe on and still not running. However took a plug out and it was soaked on top of soot that was there, so think they are useless. Dissappointed as really hoped it would fire up and start to run clean (burn deposits off the plugs) but it didnt really want to fire at all. Going to try new plugs the morrow and try. Might be something else wrong as well, worried I am barking up the wrong tree!

 

[sulzeruk]

Try not too run it too much as if it is very rich, you'll start to wash the oil of the bores and fill the sump up. They are big pistons in there and don't need much provocation to sieze. I have an S with a lovely seized bottom end which was shuffled in and out of a garage for a couple of weeks! Alasdair

 

[peanut]

I would look at the two sensors that the ECU uses to control the fuel mixture .Air temperature and water temperature (Clarks Garage have the proceedures and test readings. Also look at the AFM and check its response (good article here [link=http://www.frwilk.com/the944/afm.htm]http://www.frwilk.com/the944/afm.htm)[/link] I would also check that you havn't got any leaky injectors and that the FPV isn't stuck causing a fuel over -pressure situation

 

[diabloam]

Hmm, car fired up with new plugs but still running rough and smoking on throttle like it was, so didnt run it for long, will try the TPS and AFM plus these sensors and I might as well continue to change the rest of the vacuum hoses since I bought 30ft of 5/32" and some t-pieces. I am wondering as another possibility could the fuel regulator be faulty, forcing a higher fuel pressure in the rail. This I think would cause over fueling also, plus I have been hearing my fuel pump a little noiser than normal lately, which might point to this also. Has anbody fitted one of these adjustable fuel regulators with a built in gauge you can get off ebay from German or the USA? They look a good idea, anybody have one? Sulzeruk, Thanks for your help, got your PM, really appreciate everything, cheers all

 

[peanut]

did you actually read my previous post about the FPR ? [] yes its a distinct possibility. You can get a cheap fuel pressure gauge on ebay for around £10.00. You need to remove the nut from the fuel pressure test point on the fuel rail.( Be careful not to lose the ball bearing.) You can attach the guage using nothing more than a length of garden hose and two jubilee clips. If you leave the hose long enough you can run it into the cab and leave it attached for a few days while you monitor it. I have heard that you can use an old fashioned tyre air pressure guage which are as cheap as chips . It needs to read up to 3bar I think. Before you test the pressure try disconnecting the electrical connector to one of the fuel injectors and see if the running improves a little. If it does then its a sure thing your fuel pressure is too high one here for £18.00 posted [link=http://cgi.ebay.co.uk/FUEL-PRESSURE-GUAGE-FSE-POWER-BOOST-VALVE-0-1-BAR-/350247724955?cmd=ViewItem&pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item518c64279b]http://cgi.ebay.co.uk/FUEL-PRESSURE-GUAGE-FSE-POWER-BOOST-VALVE-0-1-BAR-/350247724955?cmd=ViewItem&pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item518c64279b[/link]

 

[diabloam]

yeah sorry missed that bit, but glad you thought of it as it could explain my problem (P.s Whats size fitting is the measure point on the rail?) I was thinking this type of thing, this one is from the states but sure I have seen german one advertised on ebay uk. http://cgi.ebay.com/ebaymotors/Porsche-944-968-911-356-912-FPR-Fuel-Pressure-Regulator-_W0QQcmdZViewItemQQhashZitem439e4061c2QQitemZ290417828290QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories Dodgy FPR would make sense of my cars symptoms, went round mates who work as mechanics to see if that pressure testing kit but had no joy. I suppose I could also get gauge from Promax as well. And also as you suggested almost any gauge that reads high enough could well do the job. Like the idea of a adjustable regulator, compact, good idea, anybody seen or have one of the ones I am on about. Peanut is there anyway of basic testing of the regulator and the pressure without a gauge, i.e. something I can tackle tomorrow in case I need to wait for bits? Thanks everybody for their advice and ideas, always welcomed

 

[peanut]

The regulator in your link is ok. You could remove your existing FPR and connect the US one and connect the fuel overflow pipe to your tank but you wouldn't be able to see the gauge unless you had your bonnet up yes you could test pressure using a tyre air pressure guage. If none of your friends Fathers have one then you can probably get one from Halfords. Seeley Tools have a proper fuel pressure guage kit with adaptors for about £18.00 You could even use the guage taken off any combination central heating boiler because they measure pressure to 3 Bar. You just need to be a bit inventive to connect it all up without losing pressure. Look on your fuel rail and you will find a huge nut . That is what you unscrew to test the pressure and the fuel flow. Don't lose the ball bearing inside the nut, it is the seal. Cover the nut and protect your eyes with glasses because the fuel is at high pressure . Use the proceedure on the Clarks Garage site to do the tests for fuel pressure and flow rate

 

[peanut]

here is a £12.00 air pressure guage from Halfords. [link=http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_566791_langId_-1_categoryId_165648]http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_566791_langId_-1_categoryId_165648[/link] I have not tested this personally but there is an article somewhere that used an air pressure guage like this. For £12.00 its surely worth a try at that price if you can't wait. Just use 2x jubilee clips and cut a 4 foot length of ordinary garden hose . The hose will fit over the threaded spigot of the fuel rail once the nut has been removed