Rjg Posted September 25, 2021 Report Share Posted September 25, 2021 Car is a 2000 2.7 boxster. Pulled into petrol station with car working perfectly. £20 worth of 98 Ron purchased and attempted to drive off. Car in limp mode with no warning lights displayed on dash, won’t rev past or even up to 2000rpm. It’s almost like I topped up with diesel but with no smoke from exhaust and the fact that I know I haven’t. The only out of normal action that occurred while at the pumps was the hood opening was activated by my daughter and the front section came down with a bit of a bump onto the windscreen catch securement. Is there anything in the hood microswitch that could cause the limp mode to activate? My OBD 11 scanner doesn’t seem to work on this production year car. TIA, Rob. Quote Link to comment Share on other sites More sharing options...
Boxob Posted September 25, 2021 Report Share Posted September 25, 2021 You could try disconnecting the battery for a while to see if it resets? (Don't forget key in position 1 before disconnecting). Quote Link to comment Share on other sites More sharing options...
edc Posted September 25, 2021 Report Share Posted September 25, 2021 I would check with the petrol station. It could be wrong fuel in their tanks or even water. Quote Link to comment Share on other sites More sharing options...
Bradders59 Posted September 25, 2021 Report Share Posted September 25, 2021 Yep, dodgy fuel. Drain the system and put some fresh stuff from a different garage in. Quote Link to comment Share on other sites More sharing options...
Paul P Posted September 25, 2021 Report Share Posted September 25, 2021 timing of event makes fuel suspect - but had similar on an audi - filled up ewith fuel - drive 800yds - car died - in my case I got a CEL and it was a coil pack but point is dont underestimate coincidence, Does it start and run clean up to 2K ? What happens at 2K - misfire ?, just doesn't rev ? I am thinking "variocam solenoid/actuator" or "throttle position sensor" or "maf" CEL only gets thrown if the computer registers "a bad thing" - if for example - it has stopped noticiing the throttle is pressed then it won't know a bad thing is happening - and a CEL is related to powertrain events around emissions typically - so misfires, mixture issues, cat operation ... Whereabouts are you - someone on here with appropriate diags with some porsche smarts might be able to find something that a generic reader won't show. Quote Link to comment Share on other sites More sharing options...
Rjg Posted September 26, 2021 Author Report Share Posted September 26, 2021 Thanks for all replies, I certainly have not ruled out the coincidence aspect of this and have ordered a new fuel filter to try first after I have drained the tank. I also have 5ltrs of 98 Ron bought from a different FS. Incidentally the original FS completely ran out of all fuel shortly after my visit so was unable to check if anyone else had experienced the same problem at any of the pumps or particularly at the one I used. On the plus side my 21 year old Boxster flew through it’s MOT with not a single advisory a fortnight ago. 😁 . 1 Quote Link to comment Share on other sites More sharing options...
MickH Posted September 26, 2021 Report Share Posted September 26, 2021 If you got the bottom of the tank that might be the issue? 1 Quote Link to comment Share on other sites More sharing options...
Rjg Posted September 30, 2021 Author Report Share Posted September 30, 2021 Finally got round to fitting the new fuel filter and putting 10 litres of fresh into the empty tank. Unfortunately no change, car starts and runs but only at very low rpm,1000 at most. I assume the fact that it is running at all means the fuel pump is ok,yes? A neighbour scanned my car with kit he uses on his Audi 7 and no codes showing. Is there any point jumping the fuel pump relay or should I be looking elsewhere now? Quote Link to comment Share on other sites More sharing options...
edc Posted September 30, 2021 Report Share Posted September 30, 2021 If it starts and idles fine but just won't rev then I would look at the throttle pedal and the throttle body Quote Link to comment Share on other sites More sharing options...
Rjg Posted September 30, 2021 Author Report Share Posted September 30, 2021 Thanks edc, I will do and clean the Maf while I’m at it but would not the throttle pedal or body throw up a fault code? Quote Link to comment Share on other sites More sharing options...
edc Posted September 30, 2021 Report Share Posted September 30, 2021 (edited) I'm not sure. I doubt they would trigger the CEL. Perhaps on a Porsche tester but not a cheaper generic obd one. Those only test mainly for generic engine protocol issues. Edited September 30, 2021 by edc Quote Link to comment Share on other sites More sharing options...
½cwt Posted September 30, 2021 Report Share Posted September 30, 2021 As @edc says another make or generic tester will only read reported emissions related faults. A duff throttle peddle potentiometer, or maybe throttle body motor won't report a fault as they are not making the engine do any thig so not causing a fault to show up. Old story - it can be hard to prove a negative. Quote Link to comment Share on other sites More sharing options...
Rjg Posted October 1, 2021 Author Report Share Posted October 1, 2021 1/2cwt, understood thanks. Sod s law that I gave up the garage that I’ve rented for the past two years last week. Having said that I don’t imagine driving 3 miles in limp mode is a good idea anyway. I’ve now got my hard top fitted which I’ll have to store in the house to allow me access to the engine bay. Doh!!!!!! Quote Link to comment Share on other sites More sharing options...
Paul P Posted October 1, 2021 Report Share Posted October 1, 2021 A scanner with Porsche smarts will be able to give you live readings of the throttle position sensor amongst other things. Car won’t log a code if it doesn’t think anything is wrong. Say for example it uses a switch to tell it the roof is closed then if the switch sticks it still thinks the roof of closed. No error, just duff info. Same with throttle sensor. a live reading will show you what the sensor is telling the car and if you move the throttle and the number doesn’t change then you can deduce the sensor isn’t responding for whatever reason. Quote Link to comment Share on other sites More sharing options...
charlieboy2608 Posted October 1, 2021 Report Share Posted October 1, 2021 The Torque app might be useful-pay £2ish for the full version Quote Link to comment Share on other sites More sharing options...
Rjg Posted October 4, 2021 Author Report Share Posted October 4, 2021 Have removed throttle body and connections in order to clean up and fit new TPS.. Which is where I have hit a snag, there is nowhere on the cars throttle body to fit a TPS on. Neither was , or at least I can’t find, there any signs of an existing TPS in the engine bay🤔 Have they been known to be located elsewhere on the car? 2000 reg 986 2.7. And why does one photo exceed the max limit allowed? Grrrr. Quote Link to comment Share on other sites More sharing options...
Paul P Posted October 4, 2021 Report Share Posted October 4, 2021 5 minutes ago, Rjg said: Have removed throttle body and connections in order to clean up and fit new TPS.. Which is where I have hit a snag, there is nowhere on the cars throttle body to fit a TPS on. Neither was , or at least I can’t find, there any signs of an existing TPS in the engine bay🤔 Have they been known to be located elsewhere on the car? 2000 reg 986 2.7. And why does one photo exceed the max limit allowed? Grrrr. I would assume the throttle position sensor is attached to the accelerator pedal ? Quote Link to comment Share on other sites More sharing options...
Paul P Posted October 4, 2021 Report Share Posted October 4, 2021 6 minutes ago, Rjg said: Have removed throttle body and connections in order to clean up and fit new TPS.. Which is where I have hit a snag, there is nowhere on the cars throttle body to fit a TPS on. Neither was , or at least I can’t find, there any signs of an existing TPS in the engine bay🤔 Have they been known to be located elsewhere on the car? 2000 reg 986 2.7. And why does one photo exceed the max limit allowed? Grrrr. Re photos - post them elsewhere on an image hosting (imgur and flickr are popular - but other I think use postimage ) - and paste the link. Keeps the hosting costs low. Quote Link to comment Share on other sites More sharing options...
Rjg Posted October 4, 2021 Author Report Share Posted October 4, 2021 Thanks for both posts Paul but aifak the accelerator pedal sensor is a different sensor which I have ordered too. The TPS is supposed to be attached to the throttle body itself, if you Google Replaceing a 986 Boxster Throttle body sensor the ensuing videos clearly show it fixed to the TB. Bit long winded , skip to 4. 30 for brevity. Quote Link to comment Share on other sites More sharing options...
Paul P Posted October 4, 2021 Report Share Posted October 4, 2021 Think that's on the very early cars by I don't have any 1st hand experience. Quote Link to comment Share on other sites More sharing options...
edc Posted October 4, 2021 Report Share Posted October 4, 2021 The 2.5 Boxster and 3.4 996 have a mechanical throttle body. The rest have a fly by wire electronic throttle. Where did you get the sensor from? Quote Link to comment Share on other sites More sharing options...
Rjg Posted October 4, 2021 Author Report Share Posted October 4, 2021 eBay edc https://www.ebay.co.uk/itm/373457425791?fits=Car+Make%3APorsche|Cars+Type%3A2.7|Cars+Year%3A2000|Model%3ABoxster&hash=item56f3cc157f:g:UqwAAOSwWf1gJdcP A much cheaper version of the above but just wanted to see if it rectified my problem. Quote Link to comment Share on other sites More sharing options...
edc Posted October 4, 2021 Report Share Posted October 4, 2021 Have you opened up the black plastic cover on the side of the throttle body with the connector? Quote Link to comment Share on other sites More sharing options...
Rjg Posted October 4, 2021 Author Report Share Posted October 4, 2021 Btw the throttle body butterfly is absolutely rigid and I’m not going to try and force it to move bit if I’ve got this right that would point to a faulty TPS , yes? Quote Link to comment Share on other sites More sharing options...
Rjg Posted October 4, 2021 Author Report Share Posted October 4, 2021 Sorry edc posted at the same time, do you mean the part that contains the motor? If so no I haven’t. Quote Link to comment Share on other sites More sharing options...
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