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Discussion Starter #1
well, it's sort one thing, and another goes to pot. It may have been going on for awhile, but I just took a long enough drive to isolate a particular issue - on throttle tip-in, sometimes, the injectors will cut out for about half a second. It seems to happen when I hit a big expansion joint in the road, but it will also do it in other situations as well. Just a short cutout. I say it's the injectors because the wideband goes lean at that moment - if it were an ignition cutout, it would go rich, possibly with a backfire.

loose injector harness? TPS sensor? Power FC just going mad, or misprogrammed? I did a full reset of the ECU and then reloaded bits of the map piece by piece. No dice.

Still lights up the EGT warning light solid until I've rolled about a hundred meters, then goes off for the remainder of the drive.

Anyone else experience this issue? It just wouldn't be my car unless I go through every possible hardware and software failure possible...:thumbsup:
 

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Is there a tps accelleration setting in the pfc?
Can the sensitivity be adjusted?

I had the exact same problem in my car. Turned out the TPS Enricment sensitivity was to low.

Or, it could be your fuelmap, maybe you got some cells you hit that need enrichment?

Asim
 

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Discussion Starter #4
good idea, I'll look at the TPS table; don't remember seeing one in FC Edit but there are a lot of tables I have no clue about :p

I actually did find a dodgy connection; one end of the injector loom, which plugs into a box mounted on the throttle cable bridge, is wiggly. I wasn't able to tighten it, but after wiggling it around the EGT light went out. But now my fuel gauge reads nearly empty...but I just topped off the tank!

Wiring gremlins. I hate them!
 

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how is the data displayed on the pfc...numbers..or as graphs(or both)? would have thought it would be tricky to miss a segment of data..
 

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Hi Toby,

Have you used the datalog function?

Activate Monitor, Map Watch and Chart. In [Map Watch - View - Dec.Places] choose for 3 or 4 for better resolution.

You have to hook up your laptop with PowerFC ecu and activate the logging by
[Map Watch - Log - Start]

Have a close look at "Advanced Inj ms" data (set it to view "Min" value) when the O2 wideband goes lean.

Hope this is helpful to give you a better insight what is going on with the injectors.

Regards,
Henk
 

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Discussion Starter #7
I'm 99% sure it's a loose contact. I still need to pull the plug off and clean the contacts and either bend out the contact springs to tighten it up, or shim the male plugs with copper foil. But after giving it a lot of wiggling, the problem has largely disappeared, and if it cutout, it was subtle enough that I could barely notice (sometimes hard bumps will jolt my foot off the accelerator!) and the couple times I thought it might have happened, it wasn't long enough to really show up on the wideband.

I wonder if my car shuns daylight like a vampire - during the day on city streets, I ran too rich on boost, but with the cooler night air, my turbos could push enough air to get my target AFRs on my map. Points to some inconsistency with my AFMs - need to pull them, give them a cleaning, maybe pull off the cover and check the solder joints and resolder if needed. Easy DIY job, just takes time.

It occurs to me that at this point, I am so far away from a "normal" driver - my car is positively ancient at this point, verging on being a true classic car, and weird engine operation is "something to be sorted at home in the garage" rather than "shit, my car is broken again". I don't know if I can go back, and live with a car that just does its job day after day. Probably a relief in one aspect (one of the things that I utterly LOVE about my bike is that I can just ride the nuts off of it without the slightest worry of it breaking, banging off the rev limiter, and I don't even think twice about any of twenty different engine parameters...other than RPM!
 
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