mattwelcer

Think i have found the problem! :D The battery! I got hold of some jumper cables and started it with the aid of my Leon and it started first time! So it would seem the battery has enough "juice" to just turn the car over and start it but not quite enough to turn it over properly. I have a C-TEK charger which i have been using to charge it. But i will now try re-conditioning it and see if that helps. If not then i guess i'll need a new battery. I'll report back in a few days after reconditioning the battery to see how it goes. Might see if i can borrow a battery of someone as well see how it starts then.

I have checked the earth strap on the gearbox and that was fine any other's i should be checking?

I assume you mean this from the VR6 cooling guide? :scratch: As I only changed all three sensors last year with new VAG parts.

OK still no luck with this problem but seem to have made a little progress. Original intake manifold (easier to check the compression later due to restricted access from the Schrick) and Airbox fitted. But the start problem was still present, also fully charged the battery and no improvement. This was all while we were having 30C here in Germany. However on Sunday the temperature dropped to 15C and hey ho the car started first time Sunday morning!!! Took it for a drive in the afternoon, parked it in the garage and came back a few hours later and the start problem was back. So I think its possibly a temperature related problem, maybe the solenoid on the starter motor isn't good. Because when the car has starting problems the car turns over and turns over then starts, if the engine is switched off and back on it starts straight away without any hesitation. Therefore could this definitely be the starter motor or could it be something else that would be affected by heat/humidity? I plan to take the starter motor out this week and take it apart to see if the carbon brushes are OK etc. How can a starter motor be tested to see if it turns over "quick enough"? As the engine does seem to turn over "slower" when starting but once the engine has started and been turned off and started again it turns over much quicker and therefore starts as expected. I hope to get a video posted too to show the start problem better.

Ok replaced the ignition switch and the additional part and no joy the start problem is still there :( So my next step will be to swap the Schrick and 57i for standard parts and then test the compression. While that's all off I will also double check the timing marks. Battery doesn't seem to be an issue either as that was charged last night but this morning made no difference what so ever :( Any other things I could try or check?

Well not been able to fit it, borrowed the special puller tool (its a Mk3 Golf) everything came apart but there is a "support ring" behind the steering lock unit which is completely crushed on one side and might explain why i have some play in the steering wheel. So new part ordered but won't be here until this afternoon...

Yeah fingers crossed, i got the new one last night just need to fit it this morning!

OK i'll get a new VAG one ordered today and see how that goes! :)

OK the ignition switch is from "Topran" and was under the impression they are OK

Yes fuel filter was replaced 2yrs ago, ignition switch wasn't a proper VAG item but an original supplier to VAG (I'll need to check the make) Edit Also forgot the injectors were also cleaned/serviced last winter too

What was the problem?

VR6 ODB2 Occasionally it starts fine first time other times it turns over for quite a while (over 5 secs) until it starts and not well at that. If after it struggling to start i turn the engine off and start it again it starts fine. This happens irrelevant to weather and irrelevant if its been stood for overnight or for 30mins. I have changed the following parts hoping that it would solve the problem; :scratch: Fuel pump Fuel Pressure Regulator Fuel lines (complete) Coilpack HT Leads Spark plugs Crank shaft sensor (in the block) There are no faults stored in memory (checked with VCDS/VAG-COM) and the battery has been checked and has been shown to be OK and fully charged. The starter was new 3 yrs ago but i am unsure how to test it other than taking it out and testing it on the bench with spare battery. What should be the next steps to localise this problem and resolve it? Can anything be monitored with VCDS to check its working as expected, is a compression test required? It does have an immobiliser and the ignition switch was replaced over a year a go. The car has the following mods, bored out to 2.9 with OEM pistons, CNC Stage 1 Cylinderhead, Schrick VGi, SP 263 cams, K&N 57i, Magnaflow cat back exhaust, Autotech lightened flywheel Any hints, tips or information on how to proceed would be greatly appreciated! (and yes i have searched the board but not found anything similar)

Looking good Jay, fingers crossed for you tomorrow for the MOT. I got my TÜV tomorrow as well at a similar time. Will you be making the trip to Wörthersee this year?

My old dampers of my Mk3 were satin and the springs were too rusty/dirty to tell, good to see you back in a Corrado!

AFAIK Early Golf VR6 4bar FPR Later Golf VR6 3bar FPR Corrado VR6 4bar FPR

Cheers Kev, with regards to a fuel pump new from VAG or else where i.e. third party? Also how much of a difference can the fuel pressure regulator make? As mine was originally a 2.8 engine (3 bar) are the later 2.9 engines the same (3 bar)or do they use a different one (4 bar)? Could this be the cause of it potentially running lean as i haven't changed this?

Just taken the engine apart due to a big end bearing failure and noticed that the valves on the cylinder head were quite white and the inside of the exhaust manifold was also white. Is this a sign of the engine running too lean and therefore running too hot? The car was originally a 2.8 which has been bored out to 2.9, it also has Schimmel 263 cams, a CNC Cylinderhead with larger inlet valves (41mm), a Schrick VGI intake and a K&N 57i intake and its a OBD2 model/ECU. I don't think those modifications would be so significant to make it run that lean. Or i am wrong and it really needs remapping ASAP to avoid any further damage? Or should i check the fuel system to see if it really is getting enough petrol? Additionally before this i had problems with a new oil cooler, where the oil and coolant were mixing. More oil getting into the coolant than the other way around. After changing the cooler to my old one it solved the problem but could this also have lead to it eventually running too hot? As with the "broken" oil cooler i had oil temps of around 108C but with the old working one the temps were around 96/98C

Yes just standard shells and no I didn't plastigauge the shell gaps as the machine shop said the crank was within tolerances. I think that's what I am going to do next try and get hold of some plastigauge and check the tolerances. When you refer to fine sand paper what grade, 1000 or finer?

Oh and an additional piece of info the engine makes the knocking noise at idle but if revved to 3000rpm and over then the knocking noise goes away. Could this therefore then just be the big end bearings and not the main bearings? And at no point did the oil warning light come on to indicate a pressure or other oil related problem.

Well last Saturday the engine started stuttering on the Autobahn while cruising at 130-140km/h after roughly 30mins. Checked oil temps and they were up at 124C so pulled over and heard knocking noises from the engine and then switched it off. Now i am pretty sure its the bearings whether its the crank or conrods i am not sure, opening it up on Friday (oil pan off). What could cause something like this to happen? I rebuilt the engine in April/May and replaced everything on it apart from the oil spray jets. The block was originally a 2.8 which i had bored out to 2.9 and used OEM Mahle 2.9 pistons. The bearings and oil pump were all new from VAG with the associated bolts. How are the conrod bearings fed with oil, through the crank from the main crank bearings? Therefore i assume it is highly likely that the main bearings are also shot if the big end bearings are shot. If i am lucky can i just replace the big end bearings provided the crank and conrods aren't scored? Or does everything need to come out and be inspected to determine the cause of the problem? Any help would be greatly appreciated as after covering 5000km (140km a day to and from work with varied motorway, dual carriage way and B roads) without any issues since it being rebuilt this has me really baffled as to why it has happened now :scratch:

:dance::dance:

Here is some additional information that might be useful. VW also have two cleaning agents for the cooling system. One to remove oil and the other rust. Here are the part no. for both G 052 188 A3 - cleaning agent for coolant circuit, deoiling (costs roughly 30€) G 111 000 A3 - cleaning agent for coolant circuit, derusting (costs roughly 40€) Both are 5ltr. and should be mixed 1:1 and then afterwards a thorough rinsing (can take several attempts!!!) should be performed to remove any left over cleaning agent. Additionally this information may only be found in the additional catalogue(s) in ETKA (to help the parts guy :thumbleft: ) Special Catalogues --> Chemical Materials --> service fluid -miscellaneous- The coolant level should them be topped up to the specified ratio using the current G12++ coolant. As far as i know the deoiling agent is orange in colour I am not sure about the derusting agent, it may be the same.

Did you have any luck with your problem and find what's causing it to run hot?

MX5 must have been a misspelling as he now has the Mk5! ;) Good to see you back on here!

Bloody hell!!! What did you do to those parts to turn them around, paint or polish? Car really does look amazing, will you be at MIVW this year? Would be good to see the car again and maybe have a chat this time!