We have a 1993 TR Magna wagon with the 2.6-litre engine and auto transmission.

Occasionally when driving up a hill, as soon as we stop accelerating, the engine stalls.

Has happened with air condition on and off.

Sometimes before this happens the car starts running real rough, juddering, etc.

The car will then start first go but usually run rough for a few seconds, then back to normal.

It doesn't stall until the throttle is closed.

Any ideas? Idle control? Fuel supply?

Thank you.

it would me more than likley be the ISC (idle speed controler), that would be my guess:D

ISC or blocked fuel line.

On your throttlebody open the butterfly and see how much carbon buildup there it. If its black on the sides of the butterfly this will most likely be the cause.

being an auto the tps (throttle position sensor) could be be way off and in need of adjustment aswell as the ics as mentioned above. when did u last clean out your pvc valve (bs) and throttle body. how olds your fuel fillter,spark plugs,dizzy cap, rotor button , leads and coil. how olds ur cat, might be blocked? theres a few things that can lead to what you described so break out the manual and go have a look:D

being an auto the tps (throttle position sensor) could be be way off and in need of adjustment aswell as the ics as mentioned above. when did u last clean out your pvc valve (bs) and throttle body. how olds your fuel fillter,spark plugs,dizzy cap, rotor button , leads and coil. how olds ur cat, might be blocked? theres a few things that can lead to what you described so break out the manual and go have a look:D

Spark plugs, dist cap and leads are near new. Cat is probably original - any easy way of checking it?

Any details on how to adjust the TPS and how to clean the PCV valve?

Does the fact that it usually shudders up the hill before stalling when the throttle is closed mean anything? And then when it restarts it shudders/runs rough for the first 10 seconds maybe?

NB. Mileage is coming up to 200,000km.

i'd be looking at the auto wiring, my tp suffered the same symptoms due to insulation break down on the solenoid wiring for the torque converter clutch

hope these help. they are for 1st gen but the engine and gearbox (astron II 4cly)are almost the same so this will work.

http://img300.imageshack.us/my.php?image=aaaoq2.jpg

http://img185.imageshack.us/my.php?image=atpskr6.jpg

http://img477.imageshack.us/my.php?image=iscmotorgd9.jpg

http://img300.imageshack.us/my.php?image=icsec0.jpg

http://img185.imageshack.us/my.php?image=idlespeedfs3.jpg

hope these help. u might need to save them to your computer and enlarge then a little . but if there that bad i'll dig out the manual and re scan the pages for u:D

Is it carby or EFI?

Is it carby or EFI?

EFI.


Thanks for all the help so far. Will update the post when I find the problem in case someone has a similar problem in the future.

Try replacing fuel filter and adjting TPS.

Otherwise sounds like a problem with the auto unfortunately.

Any details on how to adjust the TPS and how to clean the PCV valve?


The PCV valve is very easy to clean. On the top of the engine, the PCV valve is on the right with the hose coming out of it back into the plenum area. Take the hose off and unscrew the valve. Whilst you have the hose off check to make sure it doesn't have any cracks in it. These usually perish and it can cause problems if there's an air leakage! They particularly crack around its ends, but are easily replaced. Also check the hose on the other side going into the air hose, although that hose is much less likely to crack and be a problem.

With the value now out, shake it. You should hear the ball bearing inide rattle. Its a simple value design, juse a chamber with a ball bearing, that allows the flow to only go one way! Most likely it won't as they get stuck after several years. As its design you can't really stuff it up! you could try soaking it in petrol or turps to try and loosen the crap inside. Hot soapy water can also work. The best thing to use to get it clean, and don't shudder people! is over cleaner! There's two basic types of oven cleaner, the prissy non caustic one or the one that can burn your skin. Mr muscle for example comes in both, in almost identical containers. if you use that make sure its the 5 minute one! Wear kitchen gloves when you spray it. Put it up to the valve and spray, if you can use a tube from another spray can that would help! The oven cleaner cleans all the baked on fat and other crap in the oven which has been baked on with 200C+ since the last time you cleaned it, and it does the same with the inside of the valve. After letting it sit for 20 mins or so, in a bucket of hot detergent water hold the valve on its side and shake it, you need to get all the oven cleaner and crap its loosened out. Then rinse it well in fresh water. Give it a shake again and hopefully you can hear the bearing move. Now that you have all the crap off it, there's the final definitive test you can do. If you blow in the valve on one side it should flow reaonably easy, the other side side it should instantly block the air flow. If it does that its clean, and its its dry you can refit it, just ensure the hoses aren't cracked.

The other possibily is that one of your vacuum hoses is cracked, or you have a vacuum leak somewhere...

...i am still yet to understand how a dodgy PCV valve can cause the car to stall only going uphill... :nuts:

it shouldn't , i just mentioned it cos it can't hurt to clean it out, and most have never cleaned there's out. just figured if his car is struggling it probably never got maintain much in it's previous life. so it couldn't hurt and is just on more thing crossed off the service list.

I hope my explanation wasn't an arduous read! and yes, it does sound dodgy but the PVC valve is hard to damage being made of just metal, and with the massive amount of heat there the oil gets baked inside and can leave the valve permanently in a semi open position.

As the PCV valve works through a vacuum, if the hose is cracked at either end wouldn't that result in a possible loss of vacuum? Doesn't a loss of vacuum result in possible stalling...?

Hi folks, i'm new to this forum and have the same problem. My car only wants to stall uphill. Had it tested at Mitsubishi, everything seems to be fine on their computer.
Does anyone know the pressure of the fuel pump? Changed already too many parts in my car. TR, 2.6 EFI Auto. Cheers

Going uphill you have more load on the engine so the fuel regulator raises the pressure (lack of vacuum). Close the throttle the fuel pressure drops suddenly and if there is already too low fuel pressure to start with it can stall the engine. Normally while cruising or mild acceleration the O2 sensor can compensate for low pressure but at wide open throttle it goes open loop.
Either way for quick fix you could adjust the air bypass screw and the throttle stop screw for a slightly higher idle just to stop it from stalling.

Always had the feeling the car doesn't get enough fuel. Razorjack's post confirmed my guess.
Changed the fuel pressure regulator and it's up and running perfectly again.

Cheers

good too see it was sorted. i hate it when ppl ask for help and then u never hear if it was spot on or if it was fixed:D

Good stuff! Glad its all sorted out. :)

Just adding a conclusion to this post. We have put up with the problem for a long time now and after many attempts at diagnosing the problem ourselves, with the assistance of people who replied to this post, it seems to be now fixed. The fuel pressure regulator was the culprit.

Incidently when I contacted a Mitsubishi dealer to buy this part they said it was no longer available. The local auto parts store didn't have a listing for a new replacement either. Made a couple of calls to wreckers and eventually found one for $10 and one for $40. Bought the $10 one obviously.

Thanks again for the replies.

Seems I spoke too soon. The problem has come back again with a couple of weeks.

If you accelerate reasonably hard up a hill when you come to a stop it will, 3 times out 5, shudder and probably stall, and then be very hard to start, then run like crap, then be back to normal within 15 seconds or so.

The problem has now been professionally diagnosed as having sticking valves and apparently requires a cylinder head service consisting of new valve guides and whatever else they usually do.

Has anyone had this problem before and any chance you think it might be cured by an oil flush and some sort of oil additive?