idle issue

[MA70-3.0GT]

Right I've just got back from a (very cold) session of vacuum pipe route/integrity-checking & I think everything's where it should be now. One thing I did notice was that the pipe to the fuel pressure regulator was split. Lucky it was long enough to cut the knackered portion off.

Now I'm assuming (correct me if I'm wrong) that as well as increasing pressure on boost it would also be affected by vacuum at idle or lack thereof, and could be one cause of a rich condition off boost before leaning out on boost... Anyhow, I'm just waiting on batteries to charge before I go back & spin it over again and find out.

I could do with finding a new accordian pipe too as the original's got some cracks which I've sealed with tape for the moment, the damn thing's like glass!!!

[MA70-3.0GT]

Meant to say, the diag test showed code 51 (switch signal) & lists the TPS not having an IDL signal as a possible cause, or the "A/C switch. A/C circuit & A/C amplifier". What's A/C stand for in this case, not aircon obv.?...

Anyway, first chance I get I'm going to calibrate the TPS, although I can't do the timing till I can get the swine started again (Might just be out of petrol now though). Just need to find out about the A/C thing too.

EDIT-: OK so it was aircon, just never clicked that it'd be integrated into the idle circuit. Now I think of it, it has to be to bump the idleup when the compressor kicks in! Anyhow I guess the 51 is just telling me to do the TPS so I'll go do that tomorrow.

[MA70-3.0GT]

Originally Posted by MA70-3.0GT

One thing I did notice was that the pipe to the fuel pressure regulator was split....

...the fpr would also be affected by vacuum at idle or lack thereof, and could be one cause of a rich condition off boost before obviously leaning out on boost...

Anyone?... does the line to the fpr result in a lower fuel rail pressure under vacuum (i.e. at idle) or does it just serve to increase it under boost?

Either way I can't do much till Saturday (payday, roll on....) now 'cause I need to put some petrol in it...

[cre]

The reference port is used across the board to control fuel pressure whether the manifold is under vacuum or pressurized. So, yes, it lower the pressure as the manifold pressure lowers. Without the reference line connected you would run rich at vacuum and lean at boost.

[MA70-3.0GT]

Thanks, that's one problem sorted then. Actually that's quite a few problems fixed today! First off I pulled the ISCV & found bits of metal from the previous blow-up jamming the non-return valve open, cleaned that out & while the ISCV was off & I had better access to the TPS adjustment screws I set that up as well. Also I maneaged to pull all the plugs out, only having to remove the coil pack because I used a wobble bar to get at 3 & 4, the plugs were fouled to high heaven so as they were fairly new they went in the blaster & are now nice & clean.

Stuck it all back together & it runs pretty nicely now, there's still some running issues (mainly a code 31, AFM open or short) and it's still running a bit rich, possibly because of this & maybe a sticking cold start injector. Also the temp. gauge sender is dead. My biggest worry now though is that it might have the dreaded BHG as it blew all the water out after running for ten minutes.

I'm hoping that this is just a combination of a heater core leak, maybe an airlock, a sticking 'stat or just possibly a wrongly torqued head. Either way if it does turn out to need a gasket that's no real big problem (although I'd prefer to just have to burp it, obviousy!) and I'll cross that bridge as & when.

Anyhow, just to say a big thanks to cre & others who have helped me get the beast running somewhere near & ticking over (EDIT-: Sorry, idling!) reasonably well. Hopefully the paperwork will arrive in the next few days & it can come home and have the cooling system gone through & the AFM swapped over or re-wired.

Cheers, Dan.