Car still running like shit! WTF is going on?

**thechuckster** · 02-03-2009, 10:25 PM

does the FPR have a vacuum reference line going to somewhere on the manifold that's post-throttle?

some of the ports on the throttle body may be pre-plate and (if used) would give the FPR a wrong reference source for manifold vacuum

**hemi twofifteen turbo** · 03-03-2009, 12:13 AM

fuel pressure ref shouldn't matter though as running most engines (idle / off boost) with no vac connected makes minimal change (never tried it on a CA18 though) I'd say something to do with the ECU. If it's had water go in it i'd say 99% the map has changed and is the source of your problem. Can you hook up the hand controller? did your dyno guy keep a backup copy of your settings on his laptop that you could access, or maybe ask on nissan forums for a base map? I would think that if the problem started when water entered the ECU that that is where the problem is. Anyway good luck finding the gremlin.

**WHITCHY** · 03-03-2009, 07:56 AM

Yup, Hemi you're on the money! I made some phone calls yesterday to the guy who built the motor and knows CA's inside out, and he said it sounded like ECU (He also said when he puts CAs togethter he retards the exh cam 1 tooth, so it hadn't skipped!), then I rang MicroTech and he said that when they get a voltage spike through the ECU, which has obviously happened, they can reset to the base tune!

Joel (TurboRA28) Scott (ToyT18) and Mike (Regina) put in a few hours last night to check fuel pressure, and timing, then put the wideband on it, and the mixtures were stupidly lean and irratic! So Joel played with the tune a little and managed to allow it to free rev past 4k rpm! So hopefully this weekend I'll get something done about re-tuning it. Unfortunatley I don't have any copys of the tune stored to the handset! Hopefully I can find someone with a decent map for a CA18, so it doesn't have to all be done totally from scratch! It's just a pain in the ass cause the MT8 doesn't connect to a laptop, so it all needs to be done through the hand controller!

Thanks to everyone who gave advice & suggestions!

-Whitchy-

**oldcorollas** · 03-03-2009, 08:10 PM

might be a good time to put some conditioning on the power feed to the ECU.. they have a habit of dying... and if you've had one spike, it might happen again when you really don't want it to..

or a good time to change ECU

**thechuckster** · 05-03-2009, 08:57 AM

Originally Posted by hemi twofifteen turbo

fuel pressure ref shouldn't matter though as running most engines (idle / off boost) with no vac connected makes minimal change

actually, the fuel rail pressure at idle or of boost should be about half the pressure of the rail with motor off and MAP reference at 100kpa... but most motors will happily idle at stupidly rich and lean settings so this doesn't matter.

When cruising or driving off boost, a disconnected FPR will make the motor run quite rich which is not ideal in the long run.

i second Stu's suggestion of getting another ECU that's laptop tunable - even old haltechs connect to laptops (if they're running something ancient like W2K or W98).

**YLD-16L** · 05-03-2009, 09:42 AM

Originally Posted by WHITCHY

it all needs to be done through the hand controller!

Hand controller is generally quicker to tune and adjust values than lap top in the case of Microtech.

Doesn't look as pretty though.

I just got the microtech back in the mail yesterday for the 1J, apparently it was fine

I hope like in previous instances they actually did make some changes and the "it was fine" line was just BS.

**WHITCHY** · 05-03-2009, 11:47 AM

OC, what do you mean condition the power feed line? It has a fuse already.

A computer uprgade is on the horizon, I am waiting for a mate to upgrade his LT10 to an Autronic, then I get his LT. But until then I need the car running, especially for Wakefield in a few weeks! So I have to live with whats I got!

YLD, I don't think they are the most truthfull bunch at micro! I've spoken to a few people in the last week trying to sus stuff out to solve my problem, and they all had the same storys, sent the ECU back, came back with 'no issues' but magically worked!

How much do they charge when there is 'no issues'? I was charged $150 to fix the burned earth tracks, and it took about 10 days, after he told me 4! Apparently they only spend 1 day a week doing repairs!

**oldcorollas** · 05-03-2009, 12:37 PM

capacitor and choke or whatever... i'm not an elec boffin

something to reduce the spiking voltage that killed the ECU in the first place.

the ECU reset itelf cos of a power spike? then you need to put in a filter to stop those spikes, or it will just reset itself again or worse.

they are fairly fragile little ECU's and a fuse is no protection at all. a fuse just protects your battery AFTER the ECU has a poblem

fuse doesn7t protect the fused item at all (except from even more melting if it already did)

**YLD-16L** · 05-03-2009, 01:30 PM

Originally Posted by WHITCHY

OC, what do you mean condition the power feed line? It has a fuse already.

A computer uprgade is on the horizon, I am waiting for a mate to upgrade his LT10 to an Autronic, then I get his LT. But until then I need the car running, especially for Wakefield in a few weeks! So I have to live with whats I got!

YLD, I don't think they are the most truthfull bunch at micro! I've spoken to a few people in the last week trying to sus stuff out to solve my problem, and they all had the same storys, sent the ECU back, came back with 'no issues' but magically worked!

How much do they charge when there is 'no issues'? I was charged $150 to fix the burned earth tracks, and it took about 10 days, after he told me 4! Apparently they only spend 1 day a week doing repairs!

They charge $50 for no issues + postage return was $15. 2 week turnaround.