Jump to content

Engine has rough times...


topless94style

Recommended Posts

So when i bought the car on July 1 it had a small rough idle. As the days went on it got worse. Finally about a week later it would start and die. By the way this was only when the engine was cold like if i went to start it for the first time in the morning or if it had been sitting for 4hrs+. After a week of that i added more oil(o-ring leakage) filled up the tank and dumped in a can of Seafoam into the gas tank AND the crankcase. One can each. After doing so i read the directions and realized i dont need that much in either but i thought oh well cant hurt. It didnt the idle slowly got better and after a few days it was gone. Well about a week ago the idl came back and its gettin worse again. The service engine light is being tripped by something every once in a while mostly if the car has been sitting for more than 8 hrs and goes off after a couple minutes. I thought maybe EGR but that would keep a code all the time right? Then i though 02 and tried to replace but cant get at it so i figured ill look someplace else. Anyone know how to change on 02 on a 3.4L? There is also a rattling noise that comes from the cat more so when the idle is ruff than normal and u also get a stong smell of exhaust/gas mixture. Thats why i think its the 02 cuz it smells like its running rich/lean. I dont know the difference between.

 

Sorry for the length but i know that detail is important. Help is needed thanks.

Link to comment
Share on other sites

I'll bet that it is an EGR code (probably 32) that you are throwing. I throw an intermittent one when I decelerate from highway speed, and my idle is a bit crappy too. EGR codes do not have to be 'hard' codes.

It could also be a plugged cat and maybe the O2, but I'd bet that it is the EGR. If so, try giving it a clean with TB cleaner and changing the gaskets.

Jeff

1992 SP STE 3.4L

Link to comment
Share on other sites

Try unplugging the elecrtical connector to your IAC valve while your car is off. Then start it back up and see if it has a rough idle. I unplugged mine and have been driving around without for a day. My idle problems stopped. So I'll have to replace that, I think that's the problem. Anyone know if I'm gunna brake something by driving around with the IAC valve power unplugged?

Link to comment
Share on other sites

So i can i pull codes with paper clip on my car even thought its a 94? or do i have to get a code reader or someone that has one.

 

Try it see what happens. If you pull a code, it works.

If not, Slade901 was correct in saying that AutoZone does pull codes for you for free.

 

- Erik

Link to comment
Share on other sites

My bad i miss read i thought he said anyone can pull codes thats what i repeated what i said. now i get it! sorry i work overnights and im tired all the time

Link to comment
Share on other sites

Its been said my problem could be the O2 sensor. Any tips on replacing this on the 3.4L? I cant seem to get at the bastard.

 

Either from underneath the car or you'll need to pull the exhaust manifold.

 

- Erik

Link to comment
Share on other sites

Note: Because the oxygen sensor is installed in the exhaust manifold or pipe, which contracts when cool, the oxygen sensor may be very difficult to loosen when the engine is cold.

Rather than risk damage to the sensor (assuming you're planning to reuse it or perhaps just cleaning it), start and run the engine for a minute or two, then shut it off. Be careful not to burn yourself during the following procedure.

 

I recommend using an oxygen sensor socket tool.

Can't you not rotate the engine forward to get easier access to the oxygen sensor?

Link to comment
Share on other sites

Can't you not rotate the engine forward to get easier access to the oxygen sensor?

 

On a DOHC, it's possible but still there are issues with space / clearance.

Any way, or any shot you've got is a good one... extra room is a plus when working on the LQ1.

 

- Erik

Link to comment
Share on other sites

I thought about rockin the engine forward but i still cant get at it from the top. Underneath its hard to get a wrench on the damn thing because it sits on top of the exhaust pipe that is directly connected to the exhaust manifold if i remember correctly. And there is some stupid piece of metal sticking up right next to the sensor that will everyonce in a while get the wrench caught up adn just when i think im gonna put tons of pressure on the sensor it snaps loose i scrap my knuckles and scream obsenities. Ill prolly have to remove the exhaust pipe from the manifold and see where i get from there.

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.

×
×
  • Create New...