This one has me a bit stuffed....... NOT MY CAR but Neo's red 2 seater import..... http://www.aus300zx.com/forum/member.php?u=9941 links at the end of this post for history research of these issues Ian brought it to me about a month back with it running rough and we hooked up the lappy to do some basic diag's.... TPS was @0.52 (reset to 0.44 - 0.46) It would NOT sit at 0.45, it would flicker constantly at 44-46 Once it was set to the 44-46 reading it wouldnt idle below 1300rpm As a result the air screw needed to be fully screwed in to get an idle mark of 1000rpm AFM/ car actually seemed happier without an airfilter initally, but then decided it wasnt so happy and I began blocking off the afm with my fingers...... 1 finger, then 2, then 5mins later I had most of my hand covering the AFM to get a basic idle I then fitted a new pod filter and the car again was happy..... for now Sent Ian to Bryan ( O'c TV) for a closer inspection..... its called passing the buck :rofl: Bryan found 1 airleak ( I asume he fixed it) replaced all the sparkplugs checked all coils - all good checked all injectors - all good reset the TPS back to 0.52 to get an idle couldnt set the timing, to erratic - jumping all over the place:bash: discovered a bad timing belt...... engine running very lean Ian sent home ... buck passed back to me ...... :rofl: paybacks bytch So .... yesterday, whilst the GP was on , I replaced the timing belt Ian had said that there was a slight 'clicking noise' when it was cold which in the past I've discovered as being a seized belt adjuster and this then leads to the belt slaping the plastick cover...... tap tap tap tap. Sadly in this case it wasnt to be...... adjuster in excelent nick... the belt wasnt too bad either, it showed some wear but its more than servicable as a spare. The belt HAD jumped a couple of teeth tho.... The passengers bank was out 1 tooth on the exhaust cam and 2 teeth out on the inlet.... Drivers side was spot on Crank also spot on After it was all reassembled the car was started and I saw the problems from cold that Ian had described...... Struggles to idle at all Needs constant "pumping" of the throttle to keep the engine to "run" Constantly cuts out but restarts ok then runs for a minute then dies again Huge miss in the right-hand bank ( posiably 2 cylinders down) Slight backfire through AFM / pod..... barely audible for this deaf old fart (SO IT QUITE LOUD ACTUALLY ) Car is gutless to drive....... wouldnt pull grannies panties down even if the earths gravity was trebled...... it actually struggled to get back into the shed YET ....... once the temp is normal the car sits and idles ok and doesnt have the issues as bad...... the miss is still there tho but considerably less than "cold start" SO......... I've sent him home with a list ( not as big as Bryans list tho) bypass FPCU It seems very fuel related, almost as if its running out of fuel, at times even the slightest throttle increase leaves the engine to starve and die, yet a few seconds later it restarts ok..... replace unknown fuel filter It has an unknown steel bodied filter in place that requires a 5/8 heater hose to be added so the securing clamp can actually hold it CAS.... I've lent him my spare so he can fit it and see if thats the issue CAS connector is fubar but works ok.... needs replacing eventually PTU.... I seriously doubt thats a problem even tho its a series 1.... the issues are 99% when cold. Next time he comes over I'll drop in my series 2 as a tester just to be doubly sure its not the cause. AFM... Ian has fitted a new pod but bryan said it has some issues still...... Bryan can fill you in there...... ( hands back the buck :rofl I may swap mine into it as a further test next time LINKS: FPCU bypass http://www.aus300zx.com/forum/showthread.php?t=299044 poor idle when cold http://www.aus300zx.com/forum/showthread.php?t=298614 back fire issue http://www.aus300zx.com/forum/showthread.php?t=295575 any Guru's want to add to the list of posiables Kingy
I agree with zed4life, start with air regulator.... Pull the hose off and spray WD40 into the regulator, sometimes they just stick and this may free it up. If it's dead, you'll have to replace it. Reset TPS to .45 (approx) When you are adjusting "hard idle" make sure you disconnect IACV plug, otherwise you are just wasting your time. If the idle screw is in all the way, you still have a leak. If the timing belt has jumped, you may find you have some bent valves
i have the same issue with my TPS, switches between 0.44V and 0.46V at idle... is the TPS at fault or possibly wiring harness?
Correct, the scale is in .02. Possibly valves bent as Ian says, do a leak down test. Obviously check the air reg first-cheaper and easier
I think Marks on the money for the cold idle issue, but bent valves sounds like a possibility with a jumped belt. Cheers Patrick
I guess as it's the middle of the tolerance, and what Nissan designed it to be. I was always under the impression that 0.44 to 0.46V was the specified tolerance... Learn something new every day
thought the same thing.... but shouldnt it be stuck aswell when it at normal opperating temp ??? The other thing is that it does this stupid idle thing EVERY time its started cold..... cant see how the air regulator could be stuck on each occasion.... I'll add it to the list of checks to do. :bash:
havent got a fuel pressure guage ..... Oh Ian ..... Thats one of the reasons I asked him to bypass the fuel pump control unit as I've seen several of them fail on the 89 - 91 models, bad earthing leading to a dry joint on the circut board. As for supply, Ian has told me that when the filter is disconected and the supply line dangled outwards the fuel is squirted a good distance.... I'm still suspect on the actual filter, its definately not a std replacement part. You and I have been around cars long enough...... best description I can give you is an old carby engine with blocked mains and incorrectly set air screws.....slightest throttle increase leaves the engine starving and dying, you throw an old rag over the carby and the engine would be far happier..... thats what this thing is doing...... until it reaches normal opperating temp. & thats where my confusion comes in, its fine when its hot, fugly old scrag when its cold. :bash: I still feel its fuel related, main reason is that its a hot / cold issue and the engine is lean as hell at cold start...... once heat is acheived there's a component thast then able to earth or is releived to allow "normal opperation" At this stage I dont care about the miss in the right bank..... I'm after the cold start issue. fuel reg or damper added to the list :bash:
done when I did the belt again its a hot cold issue...... play wouldnt alter between hot & cold cant be so much a mechanicle thing but more an electronic issue or even electricts.......
but you would of had a rough running engine both hot and cold... unless the pipe re-connected itself when the engine had warmed up The car settles once it reaches midway on the temp guage, its almost undrivable when cold..... it would have been quicker to push it back into the shed rather than try and drive it back in yet once its warmed up ........ away we go
was a concern initally, but once i had the covers off and actully checked the marks it wasnt that bad.....1 tooth on the exhaust cam and 2 teeth out on the inlet on the left bank only...... yet I've seen 7 teeth on the crank without any damage being caused. The other thing is that the right hand bank miss is definate..... yet Ian said it was the left bank that had the miss a few weeks back.....
purple and white zeds both sit on 0.45. K1NGZ however...... 0.44 - 0.46 ........ "normal" :rofl: ----------------------------------------------------------------------- plans: Ian to do FCPU bypass Ian to do new fuel filter Ian to fit my spare CAS failing those items.... then swap over my AFM, S2 PTU, ecu then start chasing up the fuel reg / air reg after that I'll be holding a BBQ, a certain red zed will be cooking :bash: Kingy
