HELP PLEASE

[00rangerxltbadeng]

Hi! New to the site, so forgive me if this question has been answered... I just bought a 2000 Ranger xlt 4.0L. Of course, it needs a new engine... I have the chance to get a 4.0L engine from a 03 Ranger with just over 100k miles, will this fit correctly in my 2000 ranger?

 

[Dirtman]

No. In 2001 the 4.0 changed from a standard pushrod engine to an overhead cam engine. The 03 engine will physically fit but would not be a direct replacement for what you have now and would require much more work to install. (Need wiring harness and computer from the 03).

 

[00rangerxltbadeng]

Thank you so much, you just saved me from making a costly mistake! So my best bet would be to find an engine from a 2000 ranger? I was also told my catalytic converter was bad... as well as possibly the engine due to valve #1. should I get a second opinion? I was told by the previous owner the engine was rebuilt a year ago so I was shocked to hear the engine was bad.. only code that came up was p030. Any advice?

 

[00rangerxltbadeng]

*p0301

 

[Dirtman]

P0301 is a misfire code, it could be a valve issue but then all you would need is to rebuild the heads. If the valve contacted the piston to cause internal damage worthy of replacing the engine there should be alot more issues than a p0301 code. Having not looked at the engine myself or knowing what the mechanic has tested I cant be sure of anything however. A second opinion never hurts.

 

[00rangerxltbadeng]

I was kind of thinking it was odd that there’s only one code and no pending codes but was told my engine was bad without it driving terrible as well. The mechanic said that he’s not “as sure” with the engine being bad as he won’t known until he opens it up to see if the head is cracked but knows “for sure” both parts of the catalytic converters were bad because of thermal imaging showing heat.

The only tests done by the mechanic were a code reader which showed only the p0301 misfire for cylinder 1, a compression test at cylinder 1 which = 85PSI, And the thermal image which showed heat and he said is caused by the catalytic converters- both.

This is my very first project truck/ DIY, and An hour after I bought the truck the CEL came on so I ran my ODMII and it originally popped up with P0301 and p0171pending. I did research on this site and did the following things:
-Oil and filter change
-Changed all spark plugs and wiring
-Replaced front upstream left and right 02 sensors

I have no codes pending but still have the p0301 misfire at cylinder 1. I was planning on replacing the fuel injector #1 to try to resolve the issue but decided to take it to a mechanic before I started a bunch of repairs that might not even be an issue.

Any advice?? Or should I try to find a better mechanic?

 

[00rangerxltbadeng]

I also know that I have a seriously bad hose, possibly the PCV but I’m not sure what hose it exactly is... I can show a pic if you’d like, but would something as simple as a hose in this bad of shape be a cause for the misfire code?

 

[Uncle Gump]

Before you do anything else.... do a full compression test. It will confirm or negate the bad engine diagnosis.

EDIT.... There is a proper way to do a compression test... I would follow the book and do all cylinders... then make a determination about the mechanical health of the engine.

 

[Dirtman]

To get any real info from a compression test you need to do a relative test (compare all cylinders) and then a wet test (using oil to seal the rings)

85 is low either way but a wet test would say if its low because of a valve, crack or gasket, vs worn rings or cylinder. And the relative test would show you the condition of the other cylinders in comparison to see if the problem is isolated or the engine is overall worn.

The thermal test on the cats works as long as the truck was warmed up and running for a while but you should also see a codes for catalyst below threshold from the downstream o2 sensors.

The p0171 could be from the misfire. And a vacuum leak should cause a too lean condition on both banks not just one. A single cylinder misfire cant come from a systemic issue like a vacuum leak.

 

[Uncle Gump]

85 psi... was just one plug taken out... what was the cranking speed... was the throttle blocked open...

Let me ask... is there a dead miss? Or just a code?

 

[00rangerxltbadeng]

To get any real info from a compression test you need to do a relative test (compare all cylinders) and then a wet test (using oil to seal the rings)

85 is low either way but a wet test would say if its low because of a valve, crack or gasket, vs worn rings or cylinder. And the relative test would show you the condition of the other cylinders in comparison to see if the problem is isolated or the engine is overall worn.

The thermal test on the cats works as long as the truck was warmed up and running for a while but you should also see a codes for catalyst below threshold from the downstream o2 sensors.

The p0171 could be from the misfire. And a vacuum leak should cause a too lean condition on both banks not just one. A single cylinder misfire cant come from a systemic issue like a vacuum leak.

Thank you so much for the info. I will call a different mechanic and get them to do a relative test and a wet test.

Does anyone happen to know a decent mechanic here in San Diego, CA that could do that?

 

[00rangerxltbadeng]

85 psi... was just one plug taken out... what was the cranking speed... was the throttle blocked open...

Let me ask... is there a dead miss? Or just a code?

I had the mechanic do the compression test and according to what they said they appeared to only test cylinder #1.

I don’t feel like there’s a dead miss. I only notice a bit of a rough idle.... and there’s only just the code, no other pending codes or anything

 

[Uncle Gump]

I think you should just have a compression test performed... perhaps a DIY day for yourself and your new compression tester?

 

[Dirtman]

I agree with grump, you can buy a compression tester for about 30 bucks and do it yourself. If you can change a sparkplug you can do a compression test. Stores like autozone often even let you rent tools like that for no charge (just leave a deposit).

Pull all the plugs, pull the fuel pump relay out, put the gauge on one cylinder at a time and crank the engine for about 5 seconds. Write down each number. Then do it again but before attaching the gauge pour about a tablespoon full of oil in each cylinder first. Write down all the numbers again.
You will now have relative dry, and wet numbers to compare.

If the dry test shows for example 5 cylinders with 125 psi or close and one cylinder at 85, you know its an isolated issue. Do the wet test and the numbers should all go up slightly. If the low cylinder does not go up, its a head/valve issue. If the low cylinder comes up drastically, you have worn rings or a damaged cylinder.

If everything is low across the board on both tests the engine is just worn out.

My money is on a single cylinder issue with the head (leaking valve or blown gasket).

 

[00rangerxltbadeng]

Okay, I will definitely do a compression test both ways and post results. I’m going to rent the tool myself since I got quoted over $100 to perform it. But My money is also on a single cylinder issue...

my next question would be then if it is a leaking valve or a blown gasket- what then are my options for repair?