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Old 19 Aug 2007, 10:23 PM   #1 (permalink)
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hi to all and thank you for the warm welcome

i own a 98 terzo which is almost standard bar a scorpion exhaust. i have had a problem which appears to be a common scooby fault. the problem is slight hunting when warm and cold and slight hessitency on light throttle, and revs dropping at junctions( clutch in) i have so far replaced the battery, plugs and ht leads but have not cured the fault. i have also cleaned the iscv and
maf. i have also unplugged the maf but stalled instantly. i have also unplugged the lambda which seamed to cure 90% of the problem for about a day but then got worse so plugged it back in. i have checked for codes and reset more than once but nothing there. one other thing is that not long after buying the car i installed a k&n induction for about a week but took it off because i thought it ran better without it. the problems were not there before this but cant remember if this started directly after or not. from what i have read though the mafs on 98's are not as weak as the later ones so not sure if this is a possible cause? any help would be a great help, thanks in advance rich.
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Old 20 Aug 2007, 09:12 AM   #2 (permalink)
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Does sound like a possible MAF problem ??
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Old 20 Aug 2007, 09:24 AM   #3 (permalink)
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sounding like maff as pete says....
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Old 20 Aug 2007, 12:12 PM   #4 (permalink)
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thanks guys, its in my local subaru this morning (jersey) doubt they will find out whats up unless it hits them in the face but worth a try i suppose. no one over here with any real knowledge just general repairs really. this is a real pain as it costs a fortune to ferry the car to the mainland. just gonna be trial and error then if select monitor doesn't pick something up. the three main arrears for me are maf, iscv and 02 sensor but all these are serious money and a big gamble with no guarrantees. thanks again guys anyone with any other ideas?

ps one thought was oem bov? this i think would cause these symptoms? anyone
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Old 20 Aug 2007, 04:13 PM   #5 (permalink)
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you can test the maf by unplugging it when the engines running. can't remember if the cars suposed to die or stay running if you unplug it and the sensor is ok
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Old 20 Aug 2007, 06:04 PM   #6 (permalink)
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hi again just an update on the terzo.
went into subaru today and after 2.3 hrs labour at 65 yes 65 per hr this is what i have.

first of all here are the read outs of the main sensors (as they wrote it)

engine temp sensor /correct/80c - 95c/ actual/90c - 98c/ ?
iscv/ correct/20% - 50%/ actual/36% - 56% /?
0xygen sensor/correct 0v - 1.0v actual/0.50v - 0.82v/ ok
injection pulse/correct/ 2.8 +/- 0.7ms /actual/1.79ms - 2.05ms /?
maf/correct/ 0.9 +/- 0.3v/actual/ 1.08v 1.18v /?
correct 1.7 - 4.2g/s /actual/2.74g/s /?

ther were also faults on the abs which were cleared and had not come back after test run, i wonder if they were caused when i changed the discs, pads and fluid 2 weeks ago. never mentioned this to them but they said maybe abs ecu on way out?

as for the readings above what do you think? the "tech" said maf was the obvious but others dont look that good to me either. the one thats marked ok doesn't look right to m either i thought it should range from o-1v up and down not just 0.5-1.0v ?maf does seem on the right track though given the symptoms but why are all the others out of range? any ideas please, any subaru techs out there how can make anything off these. cheers rich.

sorry for the layout of the readings but when i saved the layout it changed and was very confusing so had to layout different, sorry.

Last edited by jbabrh; 20 Aug 2007 at 06:15 PM.
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