John Dixon

Bugger :eek:

CZP, $390 + shipping ($45) & taxes! Group buy?!

What price are they from courtesy Ryan?

I've got the MAF logged on my Profec E01 at the minute, which was how I saw it was on the wrong map point. Problem is still not sure whether it's dodgy sensor or leak! Might try giving it a clean though, certainly can't harm at the minute :cry:

OK, so been looking at Det again toady. Bear in mind, Thor O2 sensor clearly showed that this was leaning out not timing. This was on both my car and Leigh (Friday's) mine with various maps. So today, replaced FPR with new one (thanks Leigh) and connected up fuel pressure gauge. Result: 3bar with atmospheric on vac line, constant 3bar + boost under load, similar story on Leigh's car. So no pressure problem, but STILL DETTING! Other stuff done - EGR system disabled by removing sol valve. EGR valve works OK as applying vacuum to line when idling does make the engine run like crap. Returns to normal when pressure relased so no sticking. Possibility that valve still passes under high exhaust pressure ?? Any ideas? PVPR system removed to simplify pressure feed to FPR and remove another potential problem. Started to get a bit p'd off now so thought bugger it, will check the timing anyway. Both cars show 35° at 2000rpm! Got to thinking initially CAS is broken etc. initially adjusted Leighs to 15° which ended up with the CAS being wound right round - obviously looks wrong. From running was obviously retarded. OK, try to figure out why timing is off. Measure MAF voltage at 2000rpm, stationary gives 1.43volts. Sure enough, TP calculated at 7, which accoding to the map should give - surprise surprise 35°. So basically timing is right for engine conditions (as measured). Next measure MAF voltage at idle 1.07v, within spec of 0.8-1.5v as quoted in manual. So basically it looks like what is going on is that the MAF isn't measuring all the air going into the engine at high revs, so it's leaning out and detting. Thinking there are 3 possibilities: 1) EGR valve is passing a bit and so adding unmeterd oxygen / hot gas? 2) Air leak before turbos drawing air so it's not metering that amount. I think it would have to be a pretty big leak though. 3) MAF is a bit dodgy and is not reading the correct air flow. Any ideas / comments greatly appreciated here guys both by me and leigh ... Next step I suppose is try an new MAF :eek: or - try pinching the PCV hoses to see if idle is affected - apparently thats a way of identifying if it's an air leak.

Nothing like a bit of reasoned debate, LOL :D :D

Suspect he's in for a surprise ... :dance: :dance:

Yeah, I know but it can only adjust if there is actually time to do it. If there is 15ms time available for injection and the injectors are already open for 15ms then unless it can alter the space time continum then there's still f**k all it can do. I know what you're getting at, you can put in stupid amounts of fuel with them but only if there is actually scope to do it. It's inaccurate to say it offers 1% steps too. It offers 1% steps in the MAF signal going to the ECU, but that may/maynot give 1% enrichment, depends entirely on what the maps are doing. It's crude at best!

If they're stock callipars try changing the shims for new ones, usually cures it.

After checking (and disabling) the EGR system today, I spotted a leak from the side of my fuel pressure reg! I'm kinda hoping that it'll be the cause! Will find out tomorrow anyway ...

No, but they never set it up to run 15psi/7000rpm either! For stock boost and rev limit the injectors are absolutely fine. There is no way an AFR can add more fuel if the injectors are maxxed out. All it does is fiddle with the MAF signal to force the maps onto higher load sites. Not very clever on a Z32 anyway as it will affect the timing too. As for the Adj FPR, got one coming, but even then you have to be careful as in theory it should give 370 * (New base press / 3bar)^0.5 cc equivalent flow, but that won't hold true at high revs as the injectors will start to struggle to open against a higher pressure on the rail side, which is compounded if you run higher boost. It will definately require re-mapping otherwise the mid range will be horribly rich. The other thing to bear in mind is that these are old injectors that have opened millions of times, and there is no guarentee each injector is 370cc, some will be less, some more

Try doing the math, or connecting up a duty cycle meter then: 7300rpm, 88(decimal) TP = 98.3% Duty cycle 7300rpm, 90TP = 107.2% Duty cycle 7000rpm, 90tp = 102.8% Duty cycle. And those figures DON'T take latecy into account which is ~4% of pulse width at 90TP. TP of 90 is not unrealistic at ~1bar, and I've seen the consult duty cycle maxed out at 14psi. Also bear in mind that when running injectors at ~80% then some control is lost anyway generally.

Gangsta! Possibly the most tasteless thing I've ever seen :rofl:

Yeah, I know what you're saying about the 555's, probably is a bit OTT, but the 370's are marginal, so any slight blockage etc. could push it over the edge. It never hurts to have the reserve anyway. As for the stock AFM being restrictive, it's just a case that sucking the air through 2x 2.5" inlets instead of 1 is bound to give less pressure drop therefore better spoolup + the flow path is much cleaner. For all it costs to make one (2 bends, some pipe and another filter) then why not? I do take your point about better spending the cash though.

Better spoolup, less lag between changes, protection against det, ability to run higher boost .....

I had the fidanza one on my last car. TBH, I wouldn't say for the cost it's worth it. Better put the cash towards intercoolers or something. Dosen't really make too much difference to somoothness etc either so if you need a new flywheel anyway then you might as well get one.

Mark, Try deemon tweeks, they sell all sorts of pipe fittings and things. Either them or think automotive / james lister.

Cheers again for the ideas! Pete, thanks for the offer mate. Don't really wanna drive it very far at the minute though. TBH, I hope I can get it fixed here. Might still drop you a line yet though!

Andy, you got pm. Cheers. Just thought, I'd better check all around the intake Tee piece. I did fit an induction kit the day before the RR, so if I've bust that I could be drawing unmetered air around there somewhere I suppose.

Cheers for the replies. Andy: I'll check all the hoses I can see! Most of them have been replaced with silicon ones now so hopefully no splits etc. Ryan: I think the CAS is OK, but cheers anyway. Just thought the bracket might be misaligned by .1° or something! Clutching at straws here ...

Cheers Ryan, Might be useful just to see what all the sensors are reading etc. ECU is code 55, but something might be a little off. I've got the capibility to map on the fly, but TBH this is more than just a little off!! Just thinking that the CAS could have gone back on a bit different after doing the belt, but even then by switching to a JWT map it's dropped loads of timing off anyway. I might give you a buzz. What day are you at Pete's ?

Yep, this isn't a timing type issue, it's definately det. The timing belt is definatly right, I checked the marks several times after rotating the crank 2 turns in between. It's the first belt I'd done on one of these so was being very careful! O2 sensors are new, and not used at the sort of revs/load it's occurring at anyway. I'm thinking it's either a fuel pressure problem or a bad air leak. I've got a calibrated fuel pressure gauge so going to try that to start with. The adaptor thing you're talking about is the one Pete has. Don't bother sending it yet Pete, I'll drop you a line if I do need it, cheers.

Yep, the unit has a narrow band output to connect to the ecu to keep it happy. If you set the feedback parameter in the ECU high enough it will ignore them anyway (it does for anthing with There's a link to the site on the other post for more info.

Group Buy! In the traders section ...

No Chance! They're a heat range colder than stock and conduct heat away better. They're a protection against it if anything.