engine question

[Bob NY]

My daughter has a 2001 Ford Ranger with a 4.0L SOHC V6 engine. It was approaching 200,000 miles. These engines are known to self destruct at that point due worn timing chains and chain tensioners. She had those parts replaced. After that job was done, the engine was leaking oil from the back. There isn't enough room between the back of the engine and the firewall to tell for sure where the leak was. It did appear to be coming from higher up than the crankshaft. It was also losing coolant, but didn't leave any puddles. She thinks the oil looked cloudy. I am attaching a picture of the spark plugs. The dirty plugs are from the left bank and the clean ones are from the right bank. What conclusions can you draw from the condition of the plugs?

 

[rustred]

first thing is you have a compression problem. i am sure its higher than those readings you posted. have u done it correctly ? 5 puffs per cylinder , you should have high compression on the 3rd puff. check your gauge or connections. everyone says to have the throttle wide open but that's not necessary. left side is running richer.

 

[Stan Coryell]

Are the psi numbers compression?

I'm not familiar with the 4.0, but the fuel trims would tell you a lot. I'd consider a vacuum leak.

 

[used red MN]

My daughter has a 2001 Ford Ranger with a 4.0L SOHC V6 engine. It was approaching 200,000 miles. These engines are known to self destruct at that point due worn timing chains and chain tensioners. She had those parts replaced. After that job was done, the engine was leaking oil from the back. There isn't enough room between the back of the engine and the firewall to tell for sure where the leak was. It did appear to be coming from higher up than the crankshaft. It was also losing coolant, but didn't leave any puddles. She thinks the oil looked cloudy. I am attaching a picture of the spark plugs. The dirty plugs are from the left bank and the clean ones are from the right bank. What conclusions can you draw from the condition of the plugs?
View attachment 111257

I agree if those are compression numbers I think they are bogus. I think it is obvious the left 3 plugs show a rich mixture. I assume there is no check engine light on? Per the “fuel trim” mentioned by Stan, here is a thread in the Ranger (truck) Forums on them. The truck being discussed is a ‘99 4.0 but I am sure the general very good explanation by RF Veteran applies to your truck and many computer controlled FI vehicles.
Thread on fuel trim

 

[Sean Feeney]

Intake gasket

 

[Mcrafty1]

Intake gasket

That sounds reasonable to me also.

 

[Bob NY]

I agree if those are compression numbers I think they are bogus. I think it is obvious the left 3 plugs show a rich mixture. I assume there is no check engine light on? Per the “fuel trim” mentioned by Stan, here is a thread in the Ranger (truck) Forums on them. The truck being discussed is a ‘99 4.0 but I am sure the general very good explanation by RF Veteran applies to your truck and many computer controlled FI vehicles.
Thread on fuel trim

Thank you for the info. I read through it, but I think it is over my head. Carburetors and breaker points are more my speed. Erika, my daughter, has formal training on newer vehicles. I will share this with her, but she is working 12 hour shifts for the next 4 days, so nothing will happen until at least Thursday.

 

[used red MN]

Thank you for the info. I read through it, but I think it is over my head. Carburetors and breaker points are more my speed. Erika, my daughter, has formal training on newer vehicles. I will share this with her, but she is working 12 hour shifts for the next 4 days, so nothing will happen until at least Thursday.

Can you tell us if those psi numbers on the cardboard by the plugs were thought to be the results of a compression test?

 

[Bob NY]

Can you tell us if those psi numbers on the cardboard by the plugs were thought to be the results of a compression test?

Those are compression numbers done on the cold engine after we pulled it and turning it over with a socket and breaker bar. I don't think they are very meaningful.

 

[fusion1]

24 year old Truck with 200.000 miles
dont put alot of money into it

Ford Dealer Bob

 

[[email protected]]

If you rolled the engine over with a socket and breaker bar for a compression test, those results are not correct and should not be used as a diagnostic. Your plugs are not consistent, meaning you could have a weak coil pack or a fuel delivery issue on the darker plugs.

 

[Hemmjo]

No one has address the loosing coolant issue. Who did the work? did they have to remove the heads to do that job?

 

[Bob NY]

No one has address the loosing coolant issue. Who did the work? did they have to remove the heads to do that job?

The work was done by a guy who likes his beer a little too much. It is likely he had a few too many when he put it back together. I don't know if the heads were removed.

 

[used red MN]

Those are compression numbers done on the cold engine after we pulled it and turning it over with a socket and breaker bar. I don't think they are very meaningful.

The engine is out of the vehicle, why was it pulled because of oil leak on the back and losing coolant? Was the cooling system pressure tested before pulling the engine? It should have been. What is the intention going forward? If you intend to fix the oil leak and put it back in you definitely need an oil analysis done on the engine oil to check for coolant. If the guy liked his beer.. I assume the cost was less. Cheap is not always cheaper.

 

[rustred]

Those are compression numbers done on the cold engine after we pulled it and turning it over with a socket and breaker bar. I don't think they are very meaningful.

your thinking is correct.

 

[wore out]

My daughter has a 2001 Ford Ranger with a 4.0L SOHC V6 engine. It was approaching 200,000 miles. These engines are known to self destruct at that point due worn timing chains and chain tensioners. She had those parts replaced. After that job was done, the engine was leaking oil from the back. There isn't enough room between the back of the engine and the firewall to tell for sure where the leak was. It did appear to be coming from higher up than the crankshaft. It was also losing coolant, but didn't leave any puddles. She thinks the oil looked cloudy. I am attaching a picture of the spark plugs. The dirty plugs are from the left bank and the clean ones are from the right bank. What conclusions can you draw from the condition of the plugs?
View attachment 111257

Perhaps the "wrench" messed up the cam timing on one bank?

 

[Bob NY]

Perhaps the "wrench" messed up the cam timing on one bank?

We checked that. It is correct.