Engine power / throttle problem ?
Engine power / throttle problem ?
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Tuscain

Original Poster:

92 posts

198 months

Saturday 17th April 2010
quotequote all
Im pretty sure i saw something about this in the forums recently but cannot seem to be able to relocate it.

As the weatehr was nice today i decided to take the Tuscan down for a spin to brighton and back. Way there was perfect no problems encoutnered at all.

However on the return journey i was on the motorway, and suddenly while doing about 70 mph and not accelerating at any rate worth mentioning (ie not flooring it, but keeping constant 5th gear throttle on flat surface), the throttle suddenly become non responsive.

Immediately though not today fking trevor, and started to move into right hand lane, but luckily after about 5-10 seconds the throttle came back to life and i was able to drive back home.

Same thing happened again on offramp while decelerating, however this time throttle did not return and came to rest at full stop, felt liek power steering was gone too (quite obviously because enginge wasnt running, but weird because i didnt feel the shudder normally associated with a stall if that makes sense).

Turned hazards on, tried ti restart engine, and it did sort of kick back to lfie but rpm low(ish) at 600, then 500,400,300.... 0. Waited about 60-90 seconds, engine came back to life and didnt risk letting it die pout again so drove home and parked.

Any suggestions ?

Edited by Tuscain on Sunday 18th April 13:39

Tuscain

Original Poster:

92 posts

198 months

Sunday 18th April 2010
quotequote all
After plenty of swearing at car and killin braincells tryign to figure out this problem... Got in car this mornign and drove around for an hour on normal roads / traffic / hills / motorway and the car seemed to be runnign perfectly fine.

Suppose i will have to get ECU lead and connect to laptop to see if i can diagnose anything. Alternatively anyone near Greenwich / SE london got a lead i could use ?

PS. Been wanting to find out the "other way" of getting into car in case key fob is lost / borken. PM would be appreciated.

Cheers.

CoasTVR

25 posts

201 months

Monday 19th April 2010
quotequote all
Yeah, that was me with the same problem. And it haunted me for weeks. On all sort of occasions the throttle just fails and you have to get your car out of the way like an idiot. Very dangerous on any highway. But it also just stops in front of traffic lights etc.
I brought my car to NIMAG (which is the Dutch TVR importer) and Weynand the technician is on it as we speak. It is definitely (I hope) some electrical problem and he suspects the fuse panel having some faulty connection. I'll keep you posted on the findings. In the mean time I cannot drive the car which really is a disappointment in this great weather without any competition in the air...;-)

Buss

CoasTVR

25 posts

201 months

Thursday 22nd April 2010
quotequote all
Here is the update: The guy from NIMAG called. In the fusepanel there seems to be a relay that switches off the fuel flow to the engine (pump). In my case it caused the unexpected power loss and it also explains why it shows up in all sort of situations that are difficult to predict. The whole relaypanel has to be replaced. Hopefully tomorrow everything is Ok again.

Buss

Tuscain

Original Poster:

92 posts

198 months

Sunday 25th April 2010
quotequote all
CoasTVR said:
Here is the update: The guy from NIMAG called. In the fusepanel there seems to be a relay that switches off the fuel flow to the engine (pump). In my case it caused the unexpected power loss and it also explains why it shows up in all sort of situations that are difficult to predict. The whole relaypanel has to be replaced. Hopefully tomorrow everything is Ok again.

Buss
Do you have a rough estimate for costs as of yet ? Cheers mate.

shep1001

4,620 posts

218 months

Sunday 25th April 2010
quotequote all
Tuscain said:
CoasTVR said:
Here is the update: The guy from NIMAG called. In the fusepanel there seems to be a relay that switches off the fuel flow to the engine (pump). In my case it caused the unexpected power loss and it also explains why it shows up in all sort of situations that are difficult to predict. The whole relaypanel has to be replaced. Hopefully tomorrow everything is Ok again.

Buss
Do you have a rough estimate for costs as of yet ? Cheers mate.
The relay for the two fuel pumps is on the bottom right row of three relays on the fuse board (not the one next to the blade fuses the other side). Its a std automotive relay I dont understand why you would need to replace fuse board unless it was the board that was faulty. They cost about £25 from a TVR specialist part number is TVR M1317. I suspect if you emoved it & took it to an autofactors they would have one cheaper.

Tuscanuwe

323 posts

224 months

Monday 26th April 2010
quotequote all
The fuse board is original Porsche 993 fuse board.
So very pricy!But good quality, mine changed already also due to water
running inside panel some years ago.

Uwe

Robertjp

2,281 posts

254 months

Monday 26th April 2010
quotequote all
shep1001 said:
Tuscain said:
CoasTVR said:
Here is the update: The guy from NIMAG called. In the fusepanel there seems to be a relay that switches off the fuel flow to the engine (pump). In my case it caused the unexpected power loss and it also explains why it shows up in all sort of situations that are difficult to predict. The whole relaypanel has to be replaced. Hopefully tomorrow everything is Ok again.

Buss
Do you have a rough estimate for costs as of yet ? Cheers mate.
The relay for the two fuel pumps is on the bottom right row of three relays on the fuse board (not the one next to the blade fuses the other side). Its a std automotive relay I dont understand why you would need to replace fuse board unless it was the board that was faulty. They cost about £25 from a TVR specialist part number is TVR M1317. I suspect if you emoved it & took it to an autofactors they would have one cheaper.
"two" fuel pumps?? News to me?! (not saying your wrong, just confused by that comment!)

agree with what you say though, should only require a relay change unless the board was faulty.

CoasTVR

25 posts

201 months

Monday 26th April 2010
quotequote all
Sorry for the confusion: the relay of the fuelpump was faulty, but over time due to a bad contact in the relaypanel the plastic of the panel had melted partly. That created the unpredictable outages of the engine. Bad luck. So i had to replace it. It'll cost me about 200+ euro's. On the TVR power site you can buy the panel if you want to do the job yourself. But if your panelk is still good you only swap the relay.

Buss

shep1001

4,620 posts

218 months

Tuesday 27th April 2010
quotequote all
Robertjp said:
shep1001 said:
Tuscain said:
CoasTVR said:
Here is the update: The guy from NIMAG called. In the fusepanel there seems to be a relay that switches off the fuel flow to the engine (pump). In my case it caused the unexpected power loss and it also explains why it shows up in all sort of situations that are difficult to predict. The whole relaypanel has to be replaced. Hopefully tomorrow everything is Ok again.

Buss
Do you have a rough estimate for costs as of yet ? Cheers mate.
The relay for the two fuel pumps is on the bottom right row of three relays on the fuse board (not the one next to the blade fuses the other side). Its a std automotive relay I dont understand why you would need to replace fuse board unless it was the board that was faulty. They cost about £25 from a TVR specialist part number is TVR M1317. I suspect if you emoved it & took it to an autofactors they would have one cheaper.
"two" fuel pumps?? News to me?! (not saying your wrong, just confused by that comment!)

agree with what you say though, should only require a relay change unless the board was faulty.
Yep fuse board diagram say pump(s) so either its a typo or there is two in their. I also seem to remember a thread not to long ago which talked about their being two in the tank?

Shep