Jump to content
Ultimate Subaru Message Board

ea82 spfi high idle and sputter


Recommended Posts

when I bought the car a few weeks ago it would start okay but idle very low. was still drivable though. one night I was driving and the crank pulley came loose and the engine overheated slightly. after getting it all back together it ran the same as before, but then a few days later it began idling high and fluctuating. when I give it just a little throttle it sputters and stalls. the idle is high enough that I can actually release the clutch and take off. it still sputters though, and not safe to drive anymore. 

I'm going to check vacuum lines on my next days off. (just have to locate them all) I'm a newbie when it comes to engines but I'm here to learn. 

 

I also ordered a new coolant temp sensor, as I've seen a lot of other people on the forum have the same issue resolved by changing the part. next would be connection contacts? 

at any rate.. it's going to take some time to diagnose the problem since I have no knowledge. 

 

any help I can get is appreciated. is there any info I can share which would help diagnosis? 

thanks in advance. 

 

Link to comment
Share on other sites

Check for any codes first.  Then check basics:

-good spark ?  all plugs clean and sharp ? plug wires good ?

-distributor in good condition ?

-good fuel pressure?

-good condition of filters air/fuel ?

-check engine with vacuum gauge, I use point on engine where brake booster line connects

-good compression ?

If no codes and no problem with basics then start checking sensors.

 

 

Edited by Dee2
Link to comment
Share on other sites

12 hours ago, Dee2 said:

Check for any codes first.  Then check basics:

-good spark ?  all plugs clean and sharp ? plug wires good ?

-distributor in good condition ?

-good fuel pressure?

-good condition of filters air/fuel ?

-check engine with vacuum gauge, I use point on engine where brake booster line connects

-good compression ?

If no codes and no problem with basics then start checking sensors.

 

 

Thanks for the reply. I don't have an obd1 scan tool, but is there a way to check codes without one? 

Link to comment
Share on other sites

1 hour ago, Ionstorm66 said:

It may of skipped a tooth on the timing belt. You can pull the timing covers and just check both cams if the marks still line up.

 

Try unplugging the CTS, it's the two wire coolant sensor.

I will take it apart and check. 

 

Had the CTS unplugged for a while at operating temp and I experienced no difference. Appreciate that tip though!

Link to comment
Share on other sites

Also if the timing was adjusted it may have thrown things out of whack - there’s a set of plugs under the dashboard, above the driver’s feet that need to be connected when timing the dizzy. This stops the ECU from advancing the timing as you set it. And from what I know of the EA82 EFI systems it needs to be 20*btdc. 

Given that you overheated the EA82 it could have popped the HGs, or they were already on their way out. What compression do you have on each cylinder?

Cheers 

Bennie

Link to comment
Share on other sites

Firstly, I appreciate all the responses.

It's shifting into 4wd.

On my list:

Check timing

HGs

Compression

 

Since I had already ordered the CTS part, I put that in there and that seemed to have fixed my issues. It's running like it was before and it's driveable again.

It was really strange symptoms and it happened randomly one day and never stopped. Could the overheating have caused the very old CTS to fail somehow?

 

Since it was doing the same thing with the old CTS just unplugged, I figured maybe I wasted money but there was seriously a lot of threads on here with people having failed sensors. Their symptoms sounded exactly like mine. I'm happy at least it will drive now.

 Another problem:

When I bought it, it had a very low idle. You can hear a weird faint popping sound from the tailpipe every few seconds. The car shakes but it doesn't bother me. The tailpipe sound and shake go away with a little more RPM. It's back to it's current state with a low idle, but it doesn't stall or sputter.

Adjusting the idle speed screw seems to have no affect.

 

 

 

 

 

 

 

  • Like 1
Link to comment
Share on other sites

2 hours ago, aeox said:

Firstly, I appreciate all the responses.

It's shifting into 4wd.

On my list:

Check timing

HGs

Compression

 

Since I had already ordered the CTS part, I put that in there and that seemed to have fixed my issues. It's running like it was before and it's driveable again.

It was really strange symptoms and it happened randomly one day and never stopped. Could the overheating have caused the very old CTS to fail somehow?

 

Since it was doing the same thing with the old CTS just unplugged, I figured maybe I wasted money but there was seriously a lot of threads on here with people having failed sensors. Their symptoms sounded exactly like mine. I'm happy at least it will drive now.

 Another problem:

When I bought it, it had a very low idle. You can hear a weird faint popping sound from the tailpipe every few seconds. The car shakes but it doesn't bother me. The tailpipe sound and shake go away with a little more RPM. It's back to it's current state with a low idle, but it doesn't stall or sputter.

Adjusting the idle speed screw seems to have no affect.

 

 

 

 

 

 

 

Dose the RPM perk up with the AC on? Sounds like a vacuum leak. Also that is odd, I just went and tested, my SPFI Loyale idles fine without the CTS.

Edited by Ionstorm66
Link to comment
Share on other sites

Don’t adjust your idle screw! You’ll need to adjust your TPS to be back in spec - you’ll need a manual to tell you these details as it’s been ages since I adjusted one myself. 

Glad to hear it was the CTS, the over heat event could kill an old one easily I reckon. 

Cheers 

Bennie

Link to comment
Share on other sites

9 hours ago, el_freddo said:

Don’t adjust your idle screw! You’ll need to adjust your TPS to be back in spec - you’ll need a manual to tell you these details as it’s been ages since I adjusted one myself. 

Glad to hear it was the CTS, the over heat event could kill an old one easily I reckon. 

Cheers 

Bennie

Yep you only adjust the idle screw with the engine warmed up and the IAC unhooked.

Link to comment
Share on other sites

On 9/2/2021 at 9:10 AM, aeox said:

Firstly, I appreciate all the responses.

It's shifting into 4wd.

On my list:

Check timing

HGs

Compression

 

Since I had already ordered the CTS part, I put that in there and that seemed to have fixed my issues. It's running like it was before and it's driveable again.

It was really strange symptoms and it happened randomly one day and never stopped. Could the overheating have caused the very old CTS to fail somehow?

 

Since it was doing the same thing with the old CTS just unplugged, I figured maybe I wasted money but there was seriously a lot of threads on here with people having failed sensors. Their symptoms sounded exactly like mine. I'm happy at least it will drive now.

 Another problem:

When I bought it, it had a very low idle. You can hear a weird faint popping sound from the tailpipe every few seconds. The car shakes but it doesn't bother me. The tailpipe sound and shake go away with a little more RPM. It's back to it's current state with a low idle, but it doesn't stall or sputter.

Adjusting the idle speed screw seems to have no affect.

 

 

 

 

 

 

 

My thoughts on seeing no change, no improvement on running with CTS disconnected said to me this could be suspect. Funny how we all see things differently. Good move in ordering new, reasonably priced part before diving in elsewhere - causing more issues

  • Like 1
Link to comment
Share on other sites

I figure a +/- 30 year old CTS doesn't owe anyone much....  It's an electronic sensor that gets a thermal cycle every time you run the car.  The one I had fail since 1988 made for random crummy running & drive ability.  It wasn't out of the range limits so I had no ECU code.

  • Like 2
Link to comment
Share on other sites

  • 2 weeks later...
On 9/3/2021 at 7:25 PM, Step-a-toe said:

My thoughts on seeing no change, no improvement on running with CTS disconnected said to me this could be suspect. Funny how we all see things differently. Good move in ordering new, reasonably priced part before diving in elsewhere - causing more issues

Yea it's strange. I'm thinking that maybe the sensor reading is integral to how fuel or fuel/air is mixed in the system. With no reading at all, it just keeps cycling this horrible ratio as if it's dead cold or something. Once I replaced that sensor, every thing has been solid.

Link to comment
Share on other sites

On 9/1/2021 at 6:36 PM, Ionstorm66 said:

Dose the RPM perk up with the AC on? Sounds like a vacuum leak. Also that is odd, I just went and tested, my SPFI Loyale idles fine without the CTS.

I'm pretty sure the AC/Heat does not work :D

Edited by aeox
Link to comment
Share on other sites

On 9/1/2021 at 11:41 PM, el_freddo said:

Don’t adjust your idle screw! You’ll need to adjust your TPS to be back in spec - you’ll need a manual to tell you these details as it’s been ages since I adjusted one myself. 

Glad to hear it was the CTS, the over heat event could kill an old one easily I reckon. 

Cheers 

Bennie

I adjusted it and turned it back to where it was. Everything seems okay. I'm still needing to check for vacuum leaks. Could be any where with all these bone dry hoses!

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...