5 replies to this topic

[T-Roy]

This is my first post. Hope to improve our satisfaction with our 94 GT.

I've recently bought a '94 JDM Twin Turbo EJ20TT. Right or wrong, since we had zero knowledge of previous ownership or maintenance, we had the timing belt changed. I tell you this in case it is part of my issue? We did not drive the car more than 5 miles prior to the timing belt replacement. So we are not sure if it would have had this issue before our mechanic started work.

This car runs awesome! But after it is warmed to full operating temperatures, if we turn the AC on, our CEL comes on, has error code 66. The mechanic mentioned an imbalance of the two turbos. The result is we lose power with a quick hesitation around 2300 rpm as it goes up through each gear, like it is a limp mode disabling the turbos? If we barely accelerate up through the gears we can keep it from hesitating when this CEL is on, but any bit of wanting to go faster brings on these hesitations.

My mechanic is good, but has zero experience with TT. Is there something in the timing belt replacement he did wrong? How could turning on the AC cause this imbalance?

 

Look forward to meeting fellow Suby fans. I bought my first Subaru in Bloomington Indiana in 1984. It was a 2 door hatchback. My favorite thing of that car was the "hill holder" clutch / brake feature! I traded it in in 1987 when I special ordered a 1988 Mustang LX 5.0 5-spd T-Roof car.

Today we own 2 1996 RHD Legacy Postal Wagons, a 1994 JDM RHD TS-R 2.0 with 18,000km and a 1994 JDM RHD GT 2.0 TT with 82,000 km Dual sunroofs, leather heated seats.

 

I hope I have given enough details to get a discussion started. Thanks in advance for your help and time!

T-Roy

[duncanm]

start here: http://www.subyclub....-code-66/page-2

In particular the pdf I linked.

google 'code 66 twin turbo' - its basically time to learn all about your BBOD and how the twins operate.

I'd start by refurbing your BBOD (clean and check all solenoids)

[Josh18]

Good luck sorting it as they are great when they work. I also have a 94 GT which has needed a lot doing to it and it is worth it. First port of call is to clean out the vac lines and solenoid box. As Duncan said above, read the TT guide right through and make sure you havew an idea of how it works and know the do's and don'ts BEFORE you mess with it. It says to repalce all vacuum lines but i found mine were in good condition so I didn't replace them as the factory ones have convenient numbers on them and, as I have found, the system is very sensitive to line diameter. I just cleaned mine out along with the solenoid box with electrical cleaner and gentle compressed air. The TT guide mentions using Subaru Upper Engine Cleaner to clean the solenoids. I did this and don;t recommend it as it leaves an oily residue and mine ran like crap after that until I re-cleaned it with electrical cleaner, which fully evaporates.

Good luck with it!

[T-Roy]

Thank you for your replies!

T-Roy

[T-Roy]

My wife drove this car on Monday. Drove it all day without turning on the A/C. Not once did the CEL come on or "hesitate". I just find it odd that the only thing that will activate this CEL is to have the A/C on.

T-Roy

[Josh18]

That's really strange. Does it increase the idle speed when the air con is turned on? Mine does. Maybe if it doesn't that could cause it. Or conversely, maybe whatever makes the engine idle up when the air con is on has a short somewhere or something.