944 grinding slow starter/ lumpy tickover
Discussion
Well I'm getting a bit sick of getting the piss ripped out of me by my TVR mates due to the awful grinding start of my 1991 S2,it sounds like an old massey ferguson slogging away, oh it always starts, but never before 6 grinding, toe curling turns, and then literally bursts into life, they fall about every time and it's getting to be a spectacle.
I have read somewhere about injector seals needing to be pressurised up, and even that there is a pressure switch somewhere that will not allow ignition untill it's up to a cartain pressure, could it be something to do with either of these?.
I did think of the fuel NRV at the pump but giving it a few turns and trying again makes no diffreence, neither does turning on the ignition for a few seconds and then starting (like a diesel)
The other thing that it does is when I come up to a junction and change down the revs plummet to around 500, the engine has a lumpy stutter and then settles at a perfect tickover of about 7-800 rpm. (it never actually stalls but comes close), is this a sticky 'barn door' air metering unit?, and if so can they be stripped and cleaned/ rebuilt, I've taken to hell and toe to keep the revs up, but it can be a pain in the arse sometimes when all I want to do is go to the shops or something.
I did ask a local specialist but he said the later 944's have little or no adjustment to the injection system.
I would add it's done 113,000 miles and uses no oil at all and has been very welll looked after indeed going on it's condition, the MPG is excellent and it goes like a train, only I don't want it to keep sounding like one!.
I'd appreciate any suggestions for a bit of DIY fixing, alternatively is it worth taking it to somewhere like 9 Meister?,(I'm in the north east) or somewhere similar that really knows what they are doing (I'm reluctant to take it to my local Porsche dealer in case they just start replacing everything and end up with a bill longer than my arm).
Oh forgot to say a 'gloppering' rattle noise from the back nearside is driving me mad, it's not the drop links, bushes, shocker or anything else I can see, what do CV's sound like when they are going?, do they make a noise all the time or worse under decelleration/ around bends as mine is there all the time, like a screwdriver in the sill rattling about (actually I would have sworn it was a drop link but it's not), well thats what I've got except I've looked all over and can't see anything.
Andy.
I have read somewhere about injector seals needing to be pressurised up, and even that there is a pressure switch somewhere that will not allow ignition untill it's up to a cartain pressure, could it be something to do with either of these?.
I did think of the fuel NRV at the pump but giving it a few turns and trying again makes no diffreence, neither does turning on the ignition for a few seconds and then starting (like a diesel)
The other thing that it does is when I come up to a junction and change down the revs plummet to around 500, the engine has a lumpy stutter and then settles at a perfect tickover of about 7-800 rpm. (it never actually stalls but comes close), is this a sticky 'barn door' air metering unit?, and if so can they be stripped and cleaned/ rebuilt, I've taken to hell and toe to keep the revs up, but it can be a pain in the arse sometimes when all I want to do is go to the shops or something.
I did ask a local specialist but he said the later 944's have little or no adjustment to the injection system.
I would add it's done 113,000 miles and uses no oil at all and has been very welll looked after indeed going on it's condition, the MPG is excellent and it goes like a train, only I don't want it to keep sounding like one!.
I'd appreciate any suggestions for a bit of DIY fixing, alternatively is it worth taking it to somewhere like 9 Meister?,(I'm in the north east) or somewhere similar that really knows what they are doing (I'm reluctant to take it to my local Porsche dealer in case they just start replacing everything and end up with a bill longer than my arm).
Oh forgot to say a 'gloppering' rattle noise from the back nearside is driving me mad, it's not the drop links, bushes, shocker or anything else I can see, what do CV's sound like when they are going?, do they make a noise all the time or worse under decelleration/ around bends as mine is there all the time, like a screwdriver in the sill rattling about (actually I would have sworn it was a drop link but it's not), well thats what I've got except I've looked all over and can't see anything.
Andy.
Edited by silverS2 on Friday 6th October 17:51
i have either owned or had the use of four 944s and they all sounded like they were not going to start - particularly the 2.7lux which took about 2 seconds between each turn. they all did start however - every time. I think its a pretty common experience in 944 ownership and not something i ever worried about. smile sweetly at your TVR mates and remind yourself that your car does actually start reliably every time whereas....
Ah, Softinthehead if only life were so easy, having your mates gather round smirking expectantly as you start up, and then falling about is really no fun, okay the TVR's are pretty crappily put together but they start awesomely and sound great at the same time, and more frustratingly they have'nt fallen to bits yet (not that they ever go anywhere in them).
Any ideas about the lumpy running/ good place to get a tune up?
Andy
Any ideas about the lumpy running/ good place to get a tune up?
Andy
Most S2s do have a slow crank speed before they start but its probably down to old starter, cabling and battery as well as being a big 4 pot engine with 104mm pistons. I know a couple of S2s with new starters that don't suffer the usual malady.
Poor idling could be down to the Idle Stabiliser valve (ISV) under the intake manifold between cylinders 1 and 2. If you have small hands you can take the pipes off and improve things with a good squirt of carb cleaner which should clean up any varnish deposits. I hear of several cars having new ISVs now, I had a new one last year becuase of idle issues. It improved but wasn't perfect until a new (S/H) ecu was fitted.
9meister has an unrivalled reputation, but for 944 specialist knowledge I would recommend Hartech
Poor idling could be down to the Idle Stabiliser valve (ISV) under the intake manifold between cylinders 1 and 2. If you have small hands you can take the pipes off and improve things with a good squirt of carb cleaner which should clean up any varnish deposits. I hear of several cars having new ISVs now, I had a new one last year becuase of idle issues. It improved but wasn't perfect until a new (S/H) ecu was fitted.
9meister has an unrivalled reputation, but for 944 specialist knowledge I would recommend Hartech
Sounds like your having almost as much fun as I had with mine mate. I will ry and help you, I don't want other people making the mistakes I did!!
Firstly, the noisy start - I had the 'S' and it always started great except when the coil went (what a bast*rd that was to suss out for every Tom Dick and harry I took it to??). Point is, it always sounded a bit 'grouchy' and I'm no expert, but it sounded to me like the starter motor cog on the flywheel. Of there is excessive wear on one of them, you would get a pretty nasty noise.
On the lumpy idle. I had exactly the same problems (and worse actually). Welcome to the world of the Bosch air-flow meter. These are a complete bast*rd too. Long story short, it is knackered! You will find a few people who will tell you they can re-cpn them, but when you speak to the manufacturer like I did (I am right it is Bosch?? I don't have the car any more, you would think I'd be certain of at least this) they will tell you that the only people that can calibrate them is Bosch! They would replace the circuit board inside and re-calibrate it to obtain correct air / current bollox. Anyway they told me, if you bugger about with the spring inside the unit, you will almost certainly bugger the unit up! Which leads me to me taking it to a guy called Brian! He sorted my 205 Gti years before which had the same problems, so I thought, same type of unit, same result! WRONG. Cost me an obsolute fortune in the end! He caused no ends of problems. Don't know what he did with the Gti before, but he must have had a trick that was a simple process.
My advice is this, make sure you have a decent coil, your air meter might be OK, but if your coils isn't pumping enough Amps, it won't work properly (As I discovered).
Also, leads, make sure these are tip top condition. Also affects start up and the performance of the air-meter. I ended up with brand new leads, a known 'good coil' and a 2nd hand air meter from PorscheApart. £90 I think + del. Worked a treat.
I know I've rambled but I hope this helps! Let me know how you get on,
PS. Don't bother with main dealers, you'd be better off taking it to a VAG dealership, honestly. Especially up here. OPC Newcastle hadn't the foggiest about the 944 - too old!
Also a certain garage in teeside (specialist) don't take it to them either (mail me to tell you who it is and why not to bother, don't want to get lawyers on to me!!)
Also, if anyone needs a spare ECU for S2 or S, I have one. Never used after I bought it. Needed for the usual process of elimination method, cheers
Dave
Firstly, the noisy start - I had the 'S' and it always started great except when the coil went (what a bast*rd that was to suss out for every Tom Dick and harry I took it to??). Point is, it always sounded a bit 'grouchy' and I'm no expert, but it sounded to me like the starter motor cog on the flywheel. Of there is excessive wear on one of them, you would get a pretty nasty noise.
On the lumpy idle. I had exactly the same problems (and worse actually). Welcome to the world of the Bosch air-flow meter. These are a complete bast*rd too. Long story short, it is knackered! You will find a few people who will tell you they can re-cpn them, but when you speak to the manufacturer like I did (I am right it is Bosch?? I don't have the car any more, you would think I'd be certain of at least this) they will tell you that the only people that can calibrate them is Bosch! They would replace the circuit board inside and re-calibrate it to obtain correct air / current bollox. Anyway they told me, if you bugger about with the spring inside the unit, you will almost certainly bugger the unit up! Which leads me to me taking it to a guy called Brian! He sorted my 205 Gti years before which had the same problems, so I thought, same type of unit, same result! WRONG. Cost me an obsolute fortune in the end! He caused no ends of problems. Don't know what he did with the Gti before, but he must have had a trick that was a simple process.
My advice is this, make sure you have a decent coil, your air meter might be OK, but if your coils isn't pumping enough Amps, it won't work properly (As I discovered).
Also, leads, make sure these are tip top condition. Also affects start up and the performance of the air-meter. I ended up with brand new leads, a known 'good coil' and a 2nd hand air meter from PorscheApart. £90 I think + del. Worked a treat.
I know I've rambled but I hope this helps! Let me know how you get on,
PS. Don't bother with main dealers, you'd be better off taking it to a VAG dealership, honestly. Especially up here. OPC Newcastle hadn't the foggiest about the 944 - too old!
Also a certain garage in teeside (specialist) don't take it to them either (mail me to tell you who it is and why not to bother, don't want to get lawyers on to me!!)
Also, if anyone needs a spare ECU for S2 or S, I have one. Never used after I bought it. Needed for the usual process of elimination method, cheers
Dave
Edited by davy9449 on Friday 6th October 19:09
Andy
About your noise, I know it sounds really stupid but could it be the jack and tool set knocking against the spare wheel?
I am very much a new 944 driver and I could hear this noise that sounded like 2 pint glasses knocking against each other (not sure itthat's what yours sounds like!!) and after 48 hours worked out it was as above.
If it's not that then apologies for such a basic attempt!!
Gregor
About your noise, I know it sounds really stupid but could it be the jack and tool set knocking against the spare wheel?
I am very much a new 944 driver and I could hear this noise that sounded like 2 pint glasses knocking against each other (not sure itthat's what yours sounds like!!) and after 48 hours worked out it was as above.
If it's not that then apologies for such a basic attempt!!
Gregor
I've checked and replaced most of the electrical stuff, all in excellent condition which Iis why I thought it was on the fuel side.
It's not that it won't start or is reluctant, or even the grinding (probably tired starter/ ringear as said), it's this 6 turns before anything and then bursting into life that's getting me down.
Okay the other things (gloppering noise from the N/S rear, not the jack knocking unfortunately, it seems to be coming from the wheelarch area)and the plummeting revs/ stumbling before settling out are annoying, but it's an old car so I can live with a few things, and call them 'character', but no car engine should show no sign of firing at all, and then start on the 6th turn hot, cold or been standing for a month, that's why I thought there was something preventing it from starting (like the idea of knackered fuel injection o rings or something similar.)
can the air flow meter be cleaned?, If not I'll leave well alone.
I've had dealings with the idle stabiliser valves before in my old audi and did have some sucess, so I'll clean it out as best I can (considering where Porsche decided to put it), and I've checked for air leaks but can't see/ hear anything in the maze of pipework (would I be able to?)
Andy
It's not that it won't start or is reluctant, or even the grinding (probably tired starter/ ringear as said), it's this 6 turns before anything and then bursting into life that's getting me down.
Okay the other things (gloppering noise from the N/S rear, not the jack knocking unfortunately, it seems to be coming from the wheelarch area)and the plummeting revs/ stumbling before settling out are annoying, but it's an old car so I can live with a few things, and call them 'character', but no car engine should show no sign of firing at all, and then start on the 6th turn hot, cold or been standing for a month, that's why I thought there was something preventing it from starting (like the idea of knackered fuel injection o rings or something similar.)
can the air flow meter be cleaned?, If not I'll leave well alone.
I've had dealings with the idle stabiliser valves before in my old audi and did have some sucess, so I'll clean it out as best I can (considering where Porsche decided to put it), and I've checked for air leaks but can't see/ hear anything in the maze of pipework (would I be able to?)
Andy
Edited by silverS2 on Saturday 7th October 13:50
Edited by silverS2 on Saturday 7th October 13:52
Could someone take a picture of where the isv is in the engine as I know I need to clean mine but havent really a clue where it is and what it looks like, ta
To the original poster its also worth cleaning the leccy connectors for the AFM with contact cleaner and ensuring all the hoses are on tight with no leaks as they can both cause funny idles. AFM do come on on ebay now and again too.
To the original poster its also worth cleaning the leccy connectors for the AFM with contact cleaner and ensuring all the hoses are on tight with no leaks as they can both cause funny idles. AFM do come on on ebay now and again too.
The Idle stabization valve is bolted to the underside of the inlet manifold, you can't really miss it, well you can, because it's mostly hidden, but you do see a bit of it in between the inlet tract.
I'll tackle almost anything, but after giving it a good looking at decided not to try to get mine off due to it's position, I think I'll take the advice of taking the hoses off and squirting carb cleaner in instead.
Thanks for all the advice.
Andy.
I'll tackle almost anything, but after giving it a good looking at decided not to try to get mine off due to it's position, I think I'll take the advice of taking the hoses off and squirting carb cleaner in instead.
Thanks for all the advice.
Andy.
I seem to remember reading somewhere that the ECU is programmed to turn the engine over 5 times before it fires, this is to get some oil pressure built up before it starts. I cant remember where I read this and I can't find it again, but as all S2's that I've come across are the same I'm inclined to beleive it's true. As for it turning over slowly, again I think they all do that, think about it, you have 4 huge pistons and a high compression ratio so it's never going to spin over like a 2.0 Mondeo.
Tell you TVR mates to come back in 16 years and see how reliable their TVR's are then, that'll shut them up!!
Tell you TVR mates to come back in 16 years and see how reliable their TVR's are then, that'll shut them up!!
For the starting problem - maybe you have a dodgy immobiliser playing up?
As for the "rattle/clunking" noise, my S2 does make some noise that seems to come from the rear left wheel arch, but I eventually traced it back to something loose in the back box, which was confirmed when I got the car serviced (and was told it is nothing to worry about as the back box is working fine otherwise). Maybe you have the same?
As for the "rattle/clunking" noise, my S2 does make some noise that seems to come from the rear left wheel arch, but I eventually traced it back to something loose in the back box, which was confirmed when I got the car serviced (and was told it is nothing to worry about as the back box is working fine otherwise). Maybe you have the same?
Starting ... TADTS (They All Do That Sir)! Really. I went to look at 4 S2's before buying one, and didn't believe the first seller when he told me that they never start very well. Second seller got slightly less short shrift, third one I almost believed, and I bought the fourth one! I then went to a TIPEC meeting, and realised that EVERY S2 in the car park sounded the same when it started. If you are worried, find another one and listen to it starting - you may be surprised.
Idle? Can't help, but I'd suggest a good look at the electrics before despairing. HT leads, new plugs (when were they last changed?) coil and cap.
Thumping from behind? 944's are always noisy in the cabin, particularly from the back end. How is the gearbox oil level? Worth checking. Some people swear by Swepco, but it sounds like snake oil to me.
Of course, you could find some different mates ... ?
Oli.
Idle? Can't help, but I'd suggest a good look at the electrics before despairing. HT leads, new plugs (when were they last changed?) coil and cap.
Thumping from behind? 944's are always noisy in the cabin, particularly from the back end. How is the gearbox oil level? Worth checking. Some people swear by Swepco, but it sounds like snake oil to me.
Of course, you could find some different mates ... ?
Oli.
Not sure snake oil would be any good for differentials, surely too slippery?
I did try synthetic but binned it in favour of normal stuff, gearchange just the same, pretty good in a 'meaty, heavy' kind of way.
gloppering rattle noise sounds like a screwdriver rattling in the sill, or drop link with worn bushes, (it's worse over bumpy roads I really have tried everything to find it but have come to the conclusion that as with chris 944 s2,it may be inside the exhaust)
Immobiliser is the factory porsche one, could'nt say how to find out if it was playing up but it works OK.
zcacogp, The starting does sound as you described, I'll really have to make an effort and drag the old girl to a 944 meeting somewhere and cast an eye over a couple of others and listen to them, there seems to be little or nothing goes on in the frozen north though, all 'daan saaf'.
I did try synthetic but binned it in favour of normal stuff, gearchange just the same, pretty good in a 'meaty, heavy' kind of way.
gloppering rattle noise sounds like a screwdriver rattling in the sill, or drop link with worn bushes, (it's worse over bumpy roads I really have tried everything to find it but have come to the conclusion that as with chris 944 s2,it may be inside the exhaust)
Immobiliser is the factory porsche one, could'nt say how to find out if it was playing up but it works OK.
zcacogp, The starting does sound as you described, I'll really have to make an effort and drag the old girl to a 944 meeting somewhere and cast an eye over a couple of others and listen to them, there seems to be little or nothing goes on in the frozen north though, all 'daan saaf'.
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