I feel really bad for you. You must have spent a fortune and got very little for it and more troubles. I hate to say it but you should have done it yourself, and got it tuned by a garage at the end.
This suggests it is an electrical / ignition related fault. The fuel pumps would be affected if the fuel pump relay was "dropping out" due to losing a tach signal. As it is just momentarily misfiring though, as opposed to completely dying, I would be looking more in the ignition side of things.
I would have wondered about the hall sender if it hadn't just had a brand new dizzy (above). It's worth checking that the contacts inside the hall sender wiring plug are tight in the connector. I've seen them slip back out of the plug so they don't make proper contact.
Hi Pigbladder I'm not sure they are taking me for a ride! The issue with the stutter/misfire is so intermittant, that they could test drive the car and it would not even happen!! In their defence they have said that they will now test drive the car until the symptom happens. I have driven the car for 12+ miles and this fault has not come up and at other times it has happened within a couple of miles?? Granted they have made a few mistakes (distributor etc) but I really believe they are trying to help me out. I don't have the engine knowledge to decide if it is a misfire or some other problem, therefore I can't describe it properly to them!! Alpenweiss2
rev counter going mad would suggest something in the ign wiring , make sure the dizzy plug is clean and tight ...pull back the rubber cover and check the wires arent cracked have a look at the coil connections , they can go crusty
Also if there's been an immobiliser installed in the past, there could be some bodge wiring in the TCI-h circuit, mine had this - worth having a poke for any suspicious-looking bits wrapped up in black tape around the fusebox?
I had a go a this today and it did only take a few minutes!! The vernier pulley was set to 2 degrees retarded, so I loosened it off and adjusted to 0 degrees. Tightened it all up and took the car for a spin. It immediately felt better with more oomph lower down, but what I did notice as I drove back up the very steep hill to our house (with the window down) was a strange sort of diesel sounding (tractor-ish) noise under load??? Is this pinking? The new dizzy was fitted the other week and the timing set up? Would adjusting the vernier a couple of degrees cause the car to pink? Sorry but I'm pretty clueless on this? I also noticed that the knock sensor lead is very worn and that the insulation has broken down. Would this affect it's operation and cause the car to pink?? Also today I swapped the coil over for a spare one I had lying around. I am hoping this will cure the slight misfire I have experienced on an intermittant basis. Having said that, the last time I used the car I had no misfire?? Any advice?? Cheers Alpenweiss2
sounds like the noise may have been pinking, do you know what ignition timing the garage set? If theres too much advance it will pink, but as yours is a digi im not sure bout how good of job the knock sensor does, you could do with a cheap timing light then you could probably get it pretty well tuned on the road if you've got a good ear for pinking. I had mine 4hp off what stealth got out of it on the RR so it wasnt really worth the trip, though I have no removed my cam now as the gains dont warrant the change in drivability and lumpy idle, tbh its so much better with a std cam. Not too sure on the knock sensor wire, if its not shorting out it should be ok, but sounds like it needs sorting really.
Yes.If you change the degrees on your vernier you are changing also the ignition timing.if you go advance the ignition timing should go retard and if you go retard your ignition timing should go advance
however when you alter the camshaft timing you are altering the way the engine breathes, and hence the dynamic compression ratio. ignition timing would need to be adjusted as a result of this I would have thought, as the amount of air in the cylinders at various points in the rev range, and thus the ignition advance needed, will now be slightly different. I suppose ideally you'd recalibrate the advance curve for any major changes in camshaft timing? For now I think you should just retard the ignition bit by bit, until it stops pinking.
Hi Nick. Well after driving the car the 12 or so miles to work this morning, I definately think it is pinking! It sort of makes a ticking/clicking noise when under load?? As I have now set the cam vernier to 0 degrees what do I have to do to set up the timing correctly? I didn't realise that just adjusting the cam vernier through two degrees would cause the car to pink? Should I just adjust the cam vernier back to it's previous 2 degrees retarded and wait till I can get the car to a Rolling Road? Or can I adjust the timing by turning the dizzy, to stop the pinking (guess I will need as timing light?) I'm pretty confused now!! Cheers Alpenweiss2
Slacken the 13mm clamp bolt that holds the dizzy and turn the dizzy a few degrees clockwise. This will retard the timing slightly and see if that helps. It should.
Id be sure it was pinking its always hard to truly explain what it sounds like. Was yours a kent cam? With my piper 285 (272deg) I found 4-6deg of cam timing advance and bang on 6deg of ignition timing was good with no pinking, seems a few people have used a set up similar. Really you could do with a cheap timing gun, its really easy to check,change and set ingnition timing, you wont struggle with it. You could change the timing without one but I wouldnt recommend it as even the smallest movement changes things. So if you got a timing light just start by retarding the ignition timing till the pinking stops, just dont go bellow 6deg.
Nick is right! Sounds like the cam timing was set wrongly (as I said earlier in the thread) and too much ignition advance put on to try and compensate. Now you know how to set the cam timing you can experiment with it. Even with the vernier set at zero the cam timing will be slightly retarded due to the head being skimmed when it was flowed. Removing metal from the face of the head moves the cam and crank pulleys closer together when it's all bolted up. This then pulls the cam timing out when the cambelt is on and correctly tensioned. I'd strongly recommend trying the cam 2degs ADVANCED. No doubt you should feel another improvement! Invest in a timing light and set the ignition timing and all should be well
Thanks for the advice Chris. When I got home tonight I set the cam timing back to where it was originally (just shy of 4 degrees retarded). This is because I need to use the car alot this week and didn't want to be running around with the ignition timing out and causing pinking!! Anyway, I am back where I started and I think maybe I should wait till I can get the car to a decent RR such as Stealth..so that they set it up correctly? What do you reckon? I did speak to the guy who did the engine rebuild today and asked him why the cam timing had been set at nearly 4 degrees retarded? I also told him that many on the forum had suggested that advanced timing was the way to go! His reasoning was that with the Kent GS2H cam fitted the idle would be lumpy?? I had asked for the best idle and low down power when the engine was originally set up. From what I have been reading in the replies it sounds as though maybe the camshaft timing wasn't originally set up correctly? Why else would it need to be set up at nearly four degrees retarded? When I decided upon the GS2H for the engine, I did so because I had read widely on here that it was a civilised cam and gave a smooth idle?? How different would the GS2H be to the standard Gti cam in terms of a smooth idle? Anyway, I have a Jetex 16V stainless exhaust system on the way to be fitted to the car next week..should free up a few horses. I think I will wait till this has been fitted and then get the car set up somewhere with a rolling road? If the original timing of the cam was not done correctly, I don't know how I am going to sort it out myself? Best to leave it to the experts...any suggestions? Cheers Alpenweiss2
I just have the older version on this:http://www.diytools.co.uk/diy/Main/sp-75-4595-27902-draper-xenon-timing-light.asp it was a hand me down from the local garage when they closed and it does the job. Very easy to use and you can advance the cam to 2deg like Chris recommended and then start retarding the ignition timing little at a time until the engine performs how you want it too without pinking. Its good fun doing it yourself and means you can enjoy the car abit more before you fit the exhaust and get it on the RR. Also I think toyotech recommended tweaking the AFM by a couple of clicks, to increase the fueling, there's a thread on it somewhere.
id do what the others suggest...get a timing light and teach yourself what to do, its very easy once you get the hang of it , and it will be handy for future tune ups you should get it close enough yourself out on the road
Engine rebuild - UPDATE! Well my car is going back into the garage this week to have a nice Jetex 16 valve stanless exhaust system fitted which I bought off Funkbaron! Hopefully this will free up a bit of power and then in a few weeks I can get my car to a rolling road and get it set up properly!! I have a few issues still with the way the engine is running. At the moment the vernier timing is 4 degrees retarded and the dizzy timing is set to suit. The idle and tickover is okay but a bit lumpy? Is this down to the Kent GS2H camshaft? I am a bit concerned that the cam timing was not done spot on in the first place? If the cam was timed up using the TDC mark on the flywheel could it be out a bit? I have read that it is best to measure actual TDC using a dial gauge or other method?? Would the cam timing being out cause the lumpy idle? Also I have noticed that since the rebuild, that the engine oil temperature has been getting higher than it used to? On a short run of about 15 miles on a dual carriageway the oil temp on the MFA has been showing around 100 to 104 degrees? Is this okay? Coolant temperature seems to be fine? I have asked the garage and they say it is fine? My girlfriend's gti 8 valve only gets up to around 94-96 degrees even on a 300+ mile journey? Should I ask the garage to advance the vernier tiimg to 2 degrees afdvance and then set the dizzy correctly or will this give me a really lumpy idle? Finally, I noticed a high pitched ticking noise coming from the under the rocker cover at idle yesterday? Is this anything to worry about Lots of questions I know!! Cheers Alpenweiss2
