Gonzo’s Toolbox: Problem ‘On’ The ‘In’-Side – UnderhoodService

Gonzo’s Toolbox: Problem ‘On’ The ‘In’-Side

The tow truck came around the corner of my shop with a 2003 Focus strapped down on the bed. It's Stacey's daughter's car. Stacey is the office manager at the body shop just down the street. Her daughter's little Ford had given up at a stop sign. Now it was up to me to find out what's going on with it.



The tow truck came around the corner of my shop with a 2003 Focus strapped down on the bed. It’s Stacey’s daughter’s car. Stacey is the office manager at the body shop just down the street. Her daughter’s little Ford had given up at a stop sign. Now it was up to me to find out what’s going on with it. 

The tow driver brought the keys in to Katie (my daughter and office manager); she had already talked to Stacey and had the work order filled out.

Katie asked the tow driver, “Where did you drop it off?”

“It started for me,” the tow driver said, “so I put it along the side of the building for you.”

I found the car right where he left it and I’ll have to admit, it did start up, but I wouldn’t call it great. I made it into the service bay with it bucking, jerking and coughing like crazy, along with a terrible rotten egg smell coming from each end of the car. 

The MIL light was on, so I thought I would start with finding out which trouble codes were stored. There were P0300, P0301, P0302, P0303, P0304 and P0316 misfire codes. It’s a good thing it didn’t have any more cylinders because I’d bet it would have added them onto its list of trouble codes. Rather than get into looking at the actual data logger section of the factory scan tool, I figured I’d open the hood and see what’s going on.

The car has the 2.0L ZETEC engine. It’s a fairly easy engine to pull the spark plugs on, so I thought I would at least take a look at them. The odometer was showing 184,000 miles on this little pavement pounder, so I was thinking the worst. Anything is possible.

As I pulled off the first spark plug boot, a splash of coolant came out of the cavity. Well, that’s a little different; I didn’t quite expect that. I pulled boot #2, and the same thing happened. Then off went the next one, and again there was more coolant. When I moved onto boot #4, more coolant came flying out of the hole. 

As I peered down between the cam covers, all I could see was a sea of coolant and only the very tops of the spark plugs were sticking out. But, there were no signs of any kind of leaks anywhere on the engine. In fact, the reservoir was full and the engine showed no outward signs of overheating. It just didn’t make any sense how all this coolant could end up in there. 

I blew out all of the coolant, dried all the plug wires off and then re-installed them. After giving the key a turn, the little engine came back to life and purred like new. It was amazing how well it ran after how badly it came into the shop, but within 15 minutes or so the engine started to act up. It coughed and chugged, shacked and stuttered, and then it finally died. Now it won’t restart, what the…? What’s going on here? Time to do some more checks.

I pulled the #1 spark plug. It was very dry and very hot — exhaust gasses, I’ll bet. I let the car sit for about another 15 minutes and tried it again. A quick turn of the key and it ran like new, just as before, but this time I was ready for it. I had it hooked up to the scanner and checked out the O2 sensor readings. It was just as I suspected. The front O2 readings were a complete mess.

There was no nice oscillating wave going up and down on the screen. It was more like a jagged, old saw blade with half of its teeth missing. I watched the scope patterns for several minutes, and soon the ­engine started to cough and die just as it did before. I checked the compression this time. It was well over 200 psi — yikes I thought! Looks like all those misfires added up to a lot of raw gas going into the converter. With all the plugs firing now, the converter was only getting even more cooked than before. 

I filled Katie in on everything I had found, so she could handle it from here. I was expecting Katie to come out and tell me to order a converter, or send it to the exhaust shop or drop what I’m doing because it was going to require more time than she wanted to spend on it…something like that. But that didn’t happen. Somehow the word “IN” had more meaning to it than originally intended.

Before I knew it, a call came from Stacey, and she was going to have a new engine installed. Huh? I didn’t know I was putting a motor in; I think I missed something here. How in the world did a clogged converter turn into a new engine?

It was the very first thing Katie told Stacey. Katie said to her, “He found coolant in the spark plug area.” Even though she mentioned that I blew off all the coolant that was on the spark plugs, somehow it got turned into a leaking head gasket. (I think the guys at the body shop were helping out with the diagnostics.) It took the better part of the afternoon to get the whole thing straightened out.

Katie asked Stacey how the coolant ended up in the spark plug area. Apparently, it was from a coolant hose that split about two weeks earlier. Stacey’s daughter had someone change the hose for her, but they never thought about looking for any coolant getting trapped on top of the engine. My guess is it probably took a day or so before it ever started to miss. At that point, the service light would have come on and the real trouble would have started to build. I’ll bet she drove around with it misfiring for a week or so before she told her mom how bad it was. 

Katie explained the mix-up to me and about how everyone had the wrong idea about the engine’s condition. I can’t blame anyone for all of this. In most cases, when someone hears there is coolant “in” the engine, they assume it’s a bad deal and most likely in the combustion chamber causing major problems. Well, in this case, it was only “ON” the engine and not “IN” the engine. 

A new converter was installed and everything was back in great shape again.

I’ll make a point of explaining things a little better next time. I made the assumption that everyone knew what I meant when I said there was coolant in the spark plug area. (I should have said “on top” of the engine.)

Katie knew what I meant, but as the phone conversations went on, the word “IN” just kept pushing the coolant deeper and deeper inside this little Ford. Katie is a wonderful gal and I’ve got to hand it to her; she did a great job of explaining things. I’m a lucky guy to be able to work with my daughter in a family business, and even luckier to have her as an asset “IN” the office, especially when she can explain things to a customer and get good old Dad “OUT” of a jam.

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