EA82T Studder/Cut Off

[tundrabrat]

I am getting a studder under a moderate acceleration (like fuel starvation).

 

I noticed it for the first time a week ago as I got on a circular on-ramp and for the first 100yds down the freeway then no problem. I assumed it was because of the banking turn.

 

It occurred the second time on Saturday driving down my street (giong from 1st to 2nd), had not given it much warm up time. I let the car die and just restarted it, no other probelms.

 

Yesterday was the 3rd occurance, similar situation as Saturday.

 

Today I let the car warm up, drove up to my kids school, and was heading down the hill in 4th and it cut out again and it happened again at the bottom of the hill but I just left it in gear and it jumped itself.

 

Need help on this, car runs great and I figure it is an easy fix but want to know where I should start... Fuel filters, Plug wires, Fuel pump, Coil, Fuel injector?!?!

 

Your guys help would be appreciated!

[Gloyale]

Check the clamp on the boot where it attaches to the MAF.

[tundrabrat]

The hose clamp seems tight but I will clean the sensor and check all vaccuum lines just in case.

 

One other thing. First thing in the morning the car starts up without stepping on the gas but after it is warmed up, I usually have to give it gas when I go to start it again.

 

Don't know if that helps,

 

Ralph

[naru]

The hose clamp seems tight but I will clean the sensor and check all vaccuum lines just in case.

 

One other thing. First thing in the morning the car starts up without stepping on the gas but after it is warmed up, I usually have to give it gas when I go to start it again.

 

Don't know if that helps,

 

Ralph

 

This is almost certainly a leaky injector flooding the engine.

Might want to check the CTS too.

 

I`m having trouble understanding what the original symptoms are.

Hesitation on accel? Stalling? Shudder?

All of the above?

 

Year?

Mods?

[tundrabrat]

This is almost certainly a leaky injector flooding the engine.

Might want to check the CTS too.

 

I`m having trouble understanding what the original symptoms are.

Hesitation on accel? Stalling? Shudder?

All of the above?

 

Year?

Mods?

 

Sorry, I was all over the place with that description.

 

1.) Car starts up no problem first thing in the morning.

 

2.) After the car has started once I need to depress the accelerator to turn it over for the rest of the day... car idles fine once stared.

 

3.) Starting last week, (occasionally) under acceleration it feels like the gas just cuts out (shudder/studder) for a couple of seconds but after it does that a couple of times I don't have any additional problems during the drive.

 

4.) This afternoon the car started up just fine and then after 30 seconds (just sitting in the parking lot) it died... I turned the key and it started up again no problem.

 

'85 GL EA82T, no mods

 

I don't see a patern to this problem.

 

What's a CTS?

Edited April 9, 2012 by tundrabrat

[naru]

CTS=coolant temperature sender.

 

2. This is usually a leaky injector.

3.Hesitation on accel is most often ignition.Check wires cap rotor etc.

4.Could be many things,over/under fueling,vacuum leak,loose wire....

Seeing how #2 suggests a leaky injector maybe said injector decided to be very leaky for a moment.

[tundrabrat]

Coolant Temp Sender is an interesting idea... my temp gauge is all over the place.

 

Sometimes it is on and is reading all over the place and other times it doesn't even register. I was thinking it must be my digital dash but now I need to check into it.

 

Thanks,

 

Ralph

[desertsubaru]

Check the connector on the CTS first. They are known to get corroded and not make proper contact.

[naru]

There are 2 senders.

Engine doesn`t care about the gauge one.

Engine temp sender has 2 wires.

[tundrabrat]

Are both of the sending units located around the thermostat?

Edited April 10, 2012 by tundrabrat

[AKghandi]

The cts is right next to the egr solenoid you replaced its a 2 prong connecter on the cross pipe. Atleast thats where it was for mine not sure if yours is the same but it should be.Thats for the engine the one on the thermOstat is for the gauge and the one in the rad is for the fans

 

Maf has my vote and i believe you can take the top off yours and check the contacts there might be a bald spot around mid throttle

 

 

Sounds kinda like over boost but i know you dont drive that thing like i drive mine

[shortysayhi]

It could simply be a vacuum leak from the turbo...?

[tundrabrat]

I went through and cleaned several contacts with electrical cleaner, I sprayed around the vaccuum lines listening for any change in idle (nothing) and the car has been starting up no problem without the gas being depressed.

 

I had not problems after lunch and I drove 4 or 5 small trips

 

However, this morning it happened again once while making a left turn from a stop (accelerating from 1st to 2nd). No other problems the rest of my commute. The car had been warmed up and this happened after 10 mins of running.

 

My plan is to finish cleaning all connections (as it has probably never been done). The MAF seems like it is connected well but I will pick up some cleaner today and take care it about this afternoon.

 

I am concerned that my electrical fan isn't running but the weather has been so cool that the car has been fine. I will check thos connections this weekend... are there any tricks I should be aware of with these things?

 

I'm happy with the car... just need to go over it so I don't get left on the side of the road with a simple problem.

Edited April 10, 2012 by tundrabrat

[AKghandi]

You have the vane style maf or"flapper" maf so theres nothin really to clean but you can take it apart and see if the contact strip has any spots that have been worn through

 

Sounds like the intake pipe problem i had

Maybe when you turn left the engine flexes and the pipe pops off the turbo enough to bypass the maf. when i had the leak there i had to press the gas to get it started. And now i dont. It also would studder like your but it never did it under boost.

 

the overboost isnt controled by a boost sensor its controlled by the computer reading a lean condition

Maybe a clgged fuel filter?/16 year old gas?

 

its something simple that car was running better than mine. and you will be kicking your self for not figuring it out sooner lol

 

Also be very carful with the cts conector its very brittle from 20+years of heating up and cooling right next to the turbo

Edited April 10, 2012 by AKghandi

[tundrabrat]

I'm thnking filter... It did it again this afternoon twice withing 1 mile and then no problem for the next 15 miles.

 

When it cuts out there is literally nothing when you step on the gas for a second or two then it comes back to life.

 

Oh well... I'll get it figured out.

[AKghandi]

I got a simple test to rule out the intake pipe

 

When the cars runnIng lift up on the intake pipe to the turbo gently if its the issue the car will die.

just more random ideas that pop into my head.

 

Mine completly fell apart when i took it off and the new one i got was also cracked but not nearly as bad. its sealed with rtv epoxy and black tape now.

[tundrabrat]

Replaced the...

 

Fuel Filter

CTS

ALL Vaccum lines

Cleaned the MAF

 

The car sat for about a week while I worked on the wife's car and drove around in my 4runner. After a week of sitting it started up perfectly and drove great for the first 30 mins and then the problem started again.

 

Same thing, between 1000 and 3000 rpm I get what feels like cut out (studder) but as long as I keep it in the higher ranges (above 3000 rpm) it pulls good.

 

I will check injectors sometime this week. Let me know if you can think of anything else I should be looking at... I'll get this thing figure out!

[tundrabrat]

Cleaned all the injectors, runs a little better and starts without stepping on the gas but still have the same studder issue up to 3000rpm.

 

Wondering fuel pump, regulator or MAF?

 

Unless it gets worse I'm thinking about driving it until the Brat is done (a few more months) then just pull it off the road until I can EJ it.

[AKghandi]

i swear its that EGR solenoid. i bet they work differently between n/a and turbo.

 

the turbo one doesn't have a vent on it. but the n/a one does, this leads me to think the boost is supposed to push the EGR closed and it cant do that when its venting.

where as the n/a only sees vacuum and if it didn't vent the EGR would stay open.

 

i think the turbo one is just to keep the EGR from getting vacuum when it shouldn't, like at idle. but it does open around 1/4 throttle while cruising and not in boost to help fuel efficiency. hence the mid rpm studder

 

maybe cap off the vent? might work, and probably couldn't hurt and you do have an extra lol compare the turbo and the n/a i bet with a little ingenuity you could make it work exactly the same.

 

or ditch the egr completely. no more emissions:banana:.

 

i really hope this helps i hate to see such a clean car have such a flaw:(

that and i know its bugging the crap out of you!

 

this explains and backs my theory. and its a damn good read!

EGR Systems-how it works

[tundrabrat]

From what I have read from GD the EGR does nothing to performance, working or not as long as it is a closed system.

 

I made it over to Dwayne's yard yesterday (what a mess) and found a EA82T with the same solenoid you gave me (with the filter)... the difference between the solenoid you gave me and the one that came off of mine is that mine only has 2 wires, yours/and the one at the boneyard have 3 wires so it doesn't fit.

 

So is it spark, air or fuel. We have spark, I think air is good which is why I'm stuck on fuel... especially since the car was off the road just being moved around for the last 15 years.

 

Hope to get it figured out...

[AKghandi]

did you go to his ea82 yard? i know he had an 87 turbo there and my 87 turbo had the same solenoid as yours.

unless he did crush all the ea82t's he had. when i was there there were 6 all in a row.

 

true the egr doesn't effect performance but it does affect the air fuel ratio by leaning it out to help the mpg's while cruising

and these over boost cut when a lean condition is sensed by the ecm

im pretty sure your experiencing over-boost fuel cut. it used to happen to me in an old dodge daytona i had but it only did it because the wastegate was ruptured. and the turbo on those is pretty big compared to the subaru one so it only over boosted when i was at WOT. it would go dead for a second then come back to life. but it would do that like 4 times in a row so it was pretty violent.

 

but if it were to happen while not in boost it would be exactly the symptoms you describe just kinda goes dead for a second then comes back, randomly

 

the 02 sensor could also be suspect,it may be giving incorrect readings.

Edited May 19, 2012 by AKghandi

[WoodsWagon]

and these over boost cut when a lean condition is sensed by the ecm

im pretty sure your experiencing over-boost fuel cut.

This is not true. The 85-86 flapper door MAF cars have a boost pressure switch over on the passenger side fender that tells the ECU when it's overboosting. There's two switches right in the same bracket, one comes on at a couple psi and turns the turbo light on in the dash, the other comes on at 10 psi and tells the ECU to cut fuel. Unplug that switch and it will never cut fuel.

 

The later hot wire MAF cars hit fuel cut because the MAF is reading too much air getting pulled into the engine. This isn't a lean condition because it's still fueling to match the air coming in, but it hits fuel cut after a couple seconds of seeing the MAF voltage stay high and steady.

[AKghandi]

i stand corrected! i havent really worked on 85-86's mostly 87+

 

but wait then how do people crank up the boost on ea82t's? and not hit over boost when they still have the maf in place?.

i could've sworn i read somewhere these were lean detected boost cut. but i'm probably wrong.. wouldnt be the first time:D

[naru]

but i'm probably wrong.. wouldnt be the first time:D

 

You are right.

 

The EGR doesn`t affect the air fuel ratio by leaning it out.

EGR related MPG gains are the result of a reduction in engine pumping loss.

 

http://www.mechadyne-int.com/vva-reference/other-part-load-strategies

 

Heavy duty version:

http://www.scipio.ro/documents/96801/6bf60a29-c311-4dea-a8a7-77c71a136954

(internal EGR but same principle)

[AKghandi]

Thanks naru!

 

What if an egr were working improperly and it was to introduce excess amounts of exhaust gas for a few minutes i would think the computer would read that

As a lean condition

 

If not that then its sensing knock and pulling the timing.

 

I rode in this car before and before this problem it ran perfectly. Like a brand new car. So its got to be one simple thing causing all this frustration..