Re: How low is too low?

Posted by jimg.allentown on April 15, 2015 at 04:58:39 from (108.36.213.96):

In Reply to: How low is too low? posted by Bob N.Y. on April 14, 2015 at 16:51:07:

Bob, you never did say what engine you have in it. IIRC, it could have the 2.3 4-cylinder, the 3.0 V-6, or the 4.0 V-6.
So, I will start with the 4 cylinder. This engine used 2 spark plugs in each cylinder. So, the likelihood of a problem with the coil packs and spark plugs is somewhat reduced but still worthy of checking out. With 100 psi of compression, a head gasket is not likely. Possibly an intake manifold leak, dirty or weak injector, or a corroded connector on the injector.
For the 3.0 V-6 - These engines do have a tendency to flatten out the valve seats with high mileage. 100 psi is too low, but should not be causing a misfire code. Again, check over the basics. Look closely at the coil pack for carbon tracks or any sign of arcing. Also check the wires for any spots that may be rubbed through. Tired spark plugs can cause misfire. On rare occasions, I have seen intake manifold leaks, and in 20 years I saw exactly ONE cracked head.
Now, for the 4.0. Overall, this has been an excellent engine that is nearly impossible to wear out. It did have a few bad habits in the earlier days. There was a tendency to crack heads. I replaced quite a few on the earlier ones. 1991 to 1993 were the most affected years for that. Also, there was an issue with intake manifold gaskets getting out of place and drawing down into the valley under the manifold. Again, the obvious things like the plug wires, coil pack, and plugs are the most likely cause. I also have found corroded connectors at the fuel injectors.

Now, for the general items.....
EGR will generally cause rough running in general when it malfunctions - not a miss on a single cylinder. So, I call baloney on that one. Not likely your issue.
MAF will also affect ALL cylinders. So, I call baloney on that one too. MAF sensor is the main mixture control on the engine. When it fails, it generally does NOT set a trouble code except for a major electronic failure. More often it goes out of calibration and causes a rich or lean condition for THE WHOLE ENGINE. Not just one cylinder.
Spark plugs. The engine was designed to use platinum plugs. Hundreds of thousands of those engines have run billions of miles on platinum plugs. Now somebody wants to tell you that the engine does not like them and wants a copper core plug???? AHEM. I don't think so.
You need to concentrate on the things that are affecting #3. Injector, plug, wire, coil pack.

Replies:

• Re: How low is too low? John M 06:25:15 04/15/15 (0)
• Re: How low is too low? merlynr 06:05:40 04/15/15 (0)

Add a Reply! You must be Logged In to Post Name: E-Mail: Subject: Comments: Optional Link URL: Link Title: Optional Image URL: Optional Video Title: Optional Video URL: Advanced Posting Options Email Notification: If you check this box, email will be sent to you whenever someone replies to this message. Your email address must be entered above to receive notification. This notification will be cancelled automatically after 2 weeks.   Advanced Posting Tools   Upload Photo  Select Gallery Photo  Attach Serial No List  Return to Post  Upload Photos/Videos Choose Files from your local computer Upload one or more videos to your post. Photo filesizes should be less than 300K and Videos, less than 2MB. Formats allowed are gif, jpg, png, ogg, mp4, mov, and avi. Be sure to use filenames without spaces or special characters, and filetypes of 3 digits lower case.

TRACTOR PARTS	TRACTOR MANUALS

We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]