Occasional rough idle and wavering power while cruising

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saravarad
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Occasional rough idle and wavering power while cruising

Post by saravarad »

Hi all, I have a '92 Legacy EJ22 that I bought recently for really cheap $ and fell in love with it... the past few days though it's been acting up having some rough idle when the car warms up at the light or while decelerating sometimes and also at times while cruising at 40-50mph (that's how fast I've gone as I have driven only in town) the car tends to stall but quickly gains power and then does it in cycle for a few times... after that becomes quite normal. I have seen smoke during some of these occasions when the car tends to die and I floor it, there is a lot of smoke and car regains power.

I have taken the IACV and MAF off and cleaned them but I guess it is still not working right, going to pic-a-part this weekend to get an IACV off a scrap but apart from that can you guys think of any other things to look for? - Head gasket?

Any help would be much appreciated!!

Best Regards!! :D :mrgreen:
Legacy777
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Re: Occasional rough idle and wavering power while cruising

Post by Legacy777 »

I would suspect the MAF sensor. If you can find another one for reasonable cost, I'd suggest picking one up.

Have you checked the ECU for codes?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
saravarad
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Re: Occasional rough idle and wavering power while cruising

Post by saravarad »

Thanks for the reply! I am going to "pic a part" this weekend, will try to pick one up. I also did the MAF check that I've read in few other blogs (unplug electrical connector and yes the car shuts off in like 2-3 seconds). There is no check engine light so I didn't know if there will be any code, that still is a good idea. Will take it to autozone today/tomorrow and check for codes.

I also plan to seafoam the engine, see if a combo of newer iacv, MAF and seafoam helps. The plugs, fuel filter and air filter are all new, oil and filter are brand new. Will keep you posted.
Legacy777
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Re: Occasional rough idle and wavering power while cruising

Post by Legacy777 »

Try starting the car with the MAF sensor unplugged already.

Also, you don't need to take the car to Autozone to check the codes (actually they won't be able to check it). Instructions for checking the codes are on my site.

http://www.surrealmirage.com/subaru/engine.html
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
saravarad
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Re: Occasional rough idle and wavering power while cruising

Post by saravarad »

I read the post too late, went to pic a part and already changed both MAF and IACV before I read this post. But the good thing is, the replacement valves took care of the problem, I cleaned them both thoroughly before putting them on and 25 miles alter, still no issues of bad idles or stall. I guess I am not going to mess around with it for now.

In other news, that IACV costs $250-300 new! Got it for 7 bucks at pic-a-part, I guess they don't know the value of it. Anyway if anyone wants one of these valves, let me know. I took an extra when I was there for just in case that I don't need anymore. Will sell it for same price... No biggie ;)

Thanks for all the replies!!
Legacy777
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Re: Occasional rough idle and wavering power while cruising

Post by Legacy777 »

Do you know which one fixed your problem, MAF or IAC valve? You could stick the old MAF back in to see if the problem returns. That would help others in the future with similar problems know which one to check/replace.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
saravarad
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Re: Occasional rough idle and wavering power while cruising

Post by saravarad »

It's cold here so been lazy past few days. Will check that this weekend and post the results.
jessman1942
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Re: Occasional rough idle and wavering power while cruising

Post by jessman1942 »

this is interesting my ss does the same thing while cruising thru town you can feel very miniscule hiccups been driving me crazy i changed my maff for a really clean na one haven't changed the iac yet as legacy 777 said we would like to know :)
88 Honda civic wagon B20VTEC SWAP-RIP
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CHECK OUT MY ej20G BUILD HERE>> viewtopic.php?f=25&t=53766
saravarad
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Re: Occasional rough idle and wavering power while cruising

Post by saravarad »

Sooooo sorry for the late response guys, been living under a rock!

Anyway I tried doing A-B-A tests for both IACV and MAF and my car had problems with both interestingly. The IACV though had so much gunk in it so manually stuck but the MAF was electrically bad. Ended up replacing both.

ONE BIG WATCH OUT for everyone - IACVs are ridiculously expensive! (250-350 bucks!) please find a junk yard near you that has a car model of same year and take it off from it. I took mine from Indy Pic-a-part in Indianapolis and bought it for $8.99!! Yes 9 dollars! That's a steal! The MAF was 26 bucks but that's a bargain as well! Both came off a used scrap car that I personally took off. That car had 130k miles. My car has almost 200k!

!!!!Also another watch out!!!! - IACV has a gasket! - please buy a new one before replacing the valve! Also the breather turn to intake has several hoses hooked up to it... Be careful with those, they tend to poke you especially if they are hardened over time. Safety first!!

That's it... Thanks for all the replies guys! Hope this helps. Pls ask if you have any questions.
saravarad
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Re: Occasional rough idle and wavering power while cruising

Post by saravarad »

Typo in above post - *breather tube.. Not turn. Sorry!
Legacy777
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Re: Occasional rough idle and wavering power while cruising

Post by Legacy777 »

Have you swapped in the replacement parts yet, and if so how is the car running now?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
saravarad
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Re: Occasional rough idle and wavering power while cruising

Post by saravarad »

Replaced both parts. Car running like a champ!
Legacy777
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Re: Occasional rough idle and wavering power while cruising

Post by Legacy777 »

Good deal.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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