I often hear banter such as 'GC8' etc when talking about scooby engines. Just trying to get up to date with the lingo.

Which engines are in the classic UK impreza?

Think I know the years :
1994-96
97-99
2000
Then newage

 

Hope this helps mate

1994-96 EJ20k
97-98 EJ20G
98-00 EJ207

Afaik the newage up till 2006 also uses the EJ207 then in 2006 switched to the EJ257

Banny

 

Thats cleared things up a bit thanks.

Do you know why according to: Subaru Impreza FAQ
why the 98/99 models suffer from piston slap and 2000 doesn't? or is it just a problem they sorted out by 2000 production?

and 2001 to 2005 for that matter since they use the same engine

 

Short answer: Different metallurgy, affecting the rate of expansion and contraction of the cylinder liner and piston during warm up.

 

i had a quick read about it and understand how it happens.

But basicaly I'm looking at getting an MY00 and wanted to confirm that they do not suffer from piston slap.
i.e. the 98-00 classic uses the EJ207 engine, but did they fix the engine problem by 2000?

 

It's not really a problem anyway as long as it stops when its warmed up, normally well within 30mins.

They fixed the later cars, but the later cars had weaker MAF sensors, where if ignored causes engine failure. So you can't win

 

Nightmare I didn't know about this! What do they recomend to avoid problems? Its not an engine killer though is it?
I imagine incorrect air flow would initially cause misfires etc???


It will be a standard car so standard air filter etc

 

It can cause lean fueling on wide throttle/high boost leading to melted pistons and overloaded big-end bearings. It's a gradual failure where the sensor misreads, but doesn't always give any obvious symptoms.

Standard cars are affected too, but its more common on cars with after market filters fitted.

Its affects the post my98 classics, as these had the less reliable sensors.

 

Does anyone know if you can replace/upgrade the MAF sensors on 99/00 cars to stop this problem?

 

Yep - MAF sensor went on my MY00 a week after I bought it. I think it was about £90 for a replacement IIRC.

The Check Engine light came on during a motorway drive, engine felt like it was misfiring in 5th gear. All sorted now though.

 

I'm glad there are symtoms sometimes!!!
I've done a little reading and hear this isn't always the case though.

Guess it's just something that nedds to be replaced in servicing etc as a precaution

 

Maybe, If the cars done over 50,000 miles on the orginal or has been used with aftermarket filters, it is worth considering. Just make sure you purchase the sensor module itself and, not the whole MAF casing, as there is a HUGE difference in the price. It is claimed the replacement ones are better, but that could be just hearsay.

Remember, its a gradual failure not a total failure that causes the damage. So before it totally failing, it could have been misreading and detonating itself to death (not all detonation is audible).

 

iv got a 95 (EJ20k i think) should i worry about gettin the MAF sensor changed, iv jus had a full engine rebuild n i dont wont suttin else 2 start goin wrong, cant afford another years wages!!!

 

The MAFs on the MY00 are indeed a little fragile and should be replaced when the car starts to run erratically. Symtoms can vary but hesitation and then pulling hard are common. The good news is that a replacement cartridge on the MY00 is about £70-80 and takes only 5 mins to fit.

Mad69, why did you rebuild your engine, engine failure? if so what caused it to go? If the MAF was at fault and hasnt been diagnosed/replaced then you could be in for more trouble.