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Discussion Starter · #1 ·
I have the 99 DOHC and the engine just cuts out under acceleration. If you go real slow it doesn't happen. It happens when it is cold, not hot.
Wet weather does not seem to have anything to do with it.
When i first bought it, i was told it just needed some good gas run through it. I now have a little over 3000 miles put on it and it still does it. Every once in awhile it will also do it when warm but mostly when it is cold.

Anyone have any ideas?

Lenny

BTW..............the engine does not shut off totally. It is more like a skip than a full cutoff.
 

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Meh.
I has wagons.
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Miles on vehicle?
Known service history?
Does the CEL come on when this happens?
Is the CEL functional?
 

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(formerly) 03 H6 OBW , (presently) 06 WRX Sportwagon & 2021 Honda CR-V
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^^^^ CEL codes would be helpful. Also, after noting them, clear them and see how quickly the return.

look for a large-ish vacuum hose that goes from the IACV to under the intake 'plenum'. Though usually, the symptoms are worse if it's completely disconnected.

seems like a possibility.

Perhaps some other vacuum leak. The fact that slow application of throttle seems less severe kinda points to a vacuum leak - maybe check vacuum with a vacuum gauge.

a throttlebody cleaning might help if the IACV is sticking...I suppose it could be a TPS problem as well.

less likely Engine Temp Sensor


I might start with a vacuum gauge check and a throttlebody cleaning (like the new spray SeaFoam)
 

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96 Legacy OBW, EJ22 swap, 2" suspension lift, 215/75r15, HIDs, 06 WRX interior swap
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i like the TPM idea. aside from a vac leak IAC does nothing but control idle and wouldnt affect anything past closed throttle. does it happen at a certain throttle position? that could determine if the TPM has a bad spot. there are ways to test it with a DVOM or scan tool with datastream or something of the sort.
 

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(formerly) 03 H6 OBW , (presently) 06 WRX Sportwagon & 2021 Honda CR-V
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Seems like slow application of throttle would allow the TPS to 'linger' longer in any 'bad spot' but, who knows exactly what's happening inside there.

Still kinda wonder about vacuum though.
 

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Discussion Starter · #6 ·
Thanks very much for the responses.
The car has 131000 miles on it. The cutting out/hitching was much worse when i bought the car. It had been sitting for awhile. It got measurably better after a few good tanks of fuel but still does happen.
Not sure what CEL codes are but i own a OBDII tester and that reads DTC codes (maybe the same?). It finds nothing at all. Every once in awhile a emission vapor code comes on but i bought a new gas cap and reset the code. No change at all in the way the engine runs.
The car did not receive the best of service over its life. I know a really good mechanic friend and he has the exact same car that he drives daily. He has no idea at all what it might be. Thinks it may be fuel pressure?
The vacuum leak thing seems like it might be? Will try and hunt a leak down.

Lenny
 

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96 Legacy OBW, EJ22 swap, 2" suspension lift, 215/75r15, HIDs, 06 WRX interior swap
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I was more referring to if the slow accel is only at 50% and the heavy is at 75% throttle or more perhaps the dead spot is up higher but most commonly dead spots are at a cruise position since that's where a tps spends most of its life.

I had a vac cap fail and leak way bad. All I noticed was a loud hiss under the hood. No performance change.

CEL= check engine light. Same as OBD II codes.

Perhaps try a fuel injection service. Motorcraft makes the best one IMHO. it's a pressurized can that is hooked to the fuel rail. Pinch off the return line and pull the fuel pump relay. The car idles of the cleaner till it runs out. Works wonders if you're thinking it may
Be a gunked injector issue. Could also try one of the fuel additive type cleaners but i feel those are more to maintain not to fix an issue like you have going on.
 

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Discussion Starter · #8 ·
The slow accel is about i would say 25% throttle (is smooth) and the heavier when it cuts out/skips is about 50 to 60%. If i floor the throttle there is no skip at all......goes like **** :)
The guy i bought the car from said the fuel injectors may be a bit clogged and thought fresh gas or a cleaner would help. hmmmmmmmmmmmmmm you may have something about a fuel injection service.
 

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96 Legacy OBW, EJ22 swap, 2" suspension lift, 215/75r15, HIDs, 06 WRX interior swap
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i would say start with the injection service.

though going full throttle and having it go like it should would tell me your injectors are just fine? if they were clogged it would get worse the more load you have.

50-60% throttle and nothing else could still be TPS as that is a normal take off throttle position for our doggy cars. or perhaps MAF? im spoiled with access to a genesis scan tool and can monitor my sensors and things when i suspect a problem.
 

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96 Legacy OBW, EJ22 swap, 2" suspension lift, 215/75r15, HIDs, 06 WRX interior swap
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ya good call. i thought i had a temp sensor issue cause after my swap if you didnt let it warm up for a couple mins it was sooo doggy i almost got hit pulling in front of someone with plenty of room under normal circumstances. monitored both the temp sensors seeing as one tells the ECM and the other for the gauge both fairly close (within 10 degrees of each other) which i would consider normal.

problem has since gone away. honestly fixed itself. ha. but much diff than cut out concern.
 

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Discussion Starter · #12 ·
Sorry for the late response...............been on a trip.

Well.................the other day i let my boss borrow the car. He drove it about 45 miles round trip and put in $20.00 worth of crappy gas. I got in the car to go home...........no issue at all. I have driven the car for about a week now and it shows no issues at all. Runs great!

I asked my boss what he did and how he drove the car and everything seems normal. I honestly have no idea???????? Who would have thought. Had i known i would have let him drive the car weeks ago.................lol.

Again, thanks for all your help in trying to solve this :) Very much appreciated!

Lenny

brg
 

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(formerly) 03 H6 OBW , (presently) 06 WRX Sportwagon & 2021 Honda CR-V
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you might still consider a throttlebody cleaning, or at least run some Techron or maybe SeaFoam through a tank or 2 of gas.
 

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96 Legacy OBW, EJ22 swap, 2" suspension lift, 215/75r15, HIDs, 06 WRX interior swap
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+1 on the seafoam! worth every dang penny!
 
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