Two cars

I own a 2000 Ford Escort ZX2 with an automatic transmission. I also own a 1991 Fleetwood Cadillac with an automatic transmission. Each car has its own situation.

The ZX2 idles high (about 1000 RPM) and rumbles pretty roughly while idling. I was curious as to what the cause might be. Can anyone tell me, please?

The Cadillac has a blown head gasket and I was wondering how expensive and what would go into fixing this myself or just how much it would run going through a dealer. Any help is appreciated.

My thoughts. The ZX2 is probably suffering from an intake leak somewhere or a dirty IAC. If the CEL is on, and it should be, the codes can help steer you to a solution. If the CEL is not on, maybe a dirty throttle body is your problem. The ECM may not see a high idle as a problem if it thinks your foot is causing it. A can of throttle body cleaner (NOT CARB CLEANER!!) may be all you need.

As for the Caddy, a head gasket job at a shop will be pricey. Depending on the engine, it could run from $2,000 to $5000. Some shops may not offer to do the job. It is very labor intensive, requires sending the head(s) out to a machine shop, and takes up a lot of bay time, some of it idle until the parts come back.

However, if you have the inclination, the tools, and the time, it is a do-it-yourself project that could be rewarding. I did a Volvo BHG for my cousin. She was quoted $4500, and I did it for her in her driveway for less than $1000, but it took me 3 weekends to do it. First, start out with a good manual. The best is a factory shop manual, but a Haynes or Chiltons manual for around $20 with pictures to help guide you is a good option. They are typically designed for the DIYer and include details for a step-by-step breakdown of the entire engine. Plan on taking the head(s) to a machine shop to check for flatness and cracking, grind the valves, and replace the valve seals. Last time I did this, it cost me $300 to get the head tanked, shaved flat and re-seat 20 valves. This was pricey, because it was a Volvo DOHC. A Caddy head will be cheaper. Hint, the valve seals are generally part of a head gasket kit, so make sure you get that first. They range from $80 to $150, depending on engine.

Tips to offer include using masking tape and a sharpie to mark ALL WIRES AND VACUUM HOSES at both ends that need to be disconnected as you go. This makes reassembly a breeze. If the head bolts require a final torque angle, replace them with new before reassembly. These are torque-to-yeild bolts and cannot be re-used. Drain the coolant, but leave the engine oil. Change the engine oil before you try and start the car, so any contaminants that may have dripped down in the crankcase can be removed with the oil. If the oil is milky, plan on an oil change and coolant flush-n-fill about 100 miles after a successful repair to help clean out the rest of the mess.

Also, pay attention to things you can reach while doing this. Certain seals, hoses, and belts could probably stand to be replaced that may not be included in the kit. I’ve found it is best to replace this stuff when it is easier to get to, since I’m already down in there.

I would dump the Cadillac; unless you are a mechanic, it will be very difficult and expensive in time and parts for you to do it yourself. A Cadillac that age will soon have other expensive problems, making your life even more miserable.

The Escort is fixable at reasonable cost, and I would shop around for a good independent mechanic.

Almost all Escorts idle a little bit rough (I own 5 or them), especially if the a/c is turned on or if it’s an automatic transmission and is idling in gear. Try turning the a/c off and sliding the transmission into neutral to see if it smooths out. If it smooths out it’s probably just that the idle speed doesn’t rise enough to compensate for the extra load on the engine. If it doesn’t smooth out then you may need a tune up or the IAC valve and MAF sensor could need cleaning.

BustedKnuckles: Thank you! Your post was actually incredibly informative. The Check Engine Light is not on. Are there any warnings concerning Throttle Body Cleaner? As for the Cadi; I intend to just sell the machine. It’s been a wonderful car for me, but it has seen better days and I feel like I could just sell it for parts or to a mechanic who needs it for a class or for someone who enjoys fix-it-up projects.

Docnick: Thanks for your opinion. I’m probably going to do just that and sell it. As for the Escort, I believe that almost all issues with it I can fix myself.

FordMan59: It does smooth out after putting it into neutral, turning the AC off doesn’t help at all though.

Other notes: I was told that the PCV valve might be the cause of the rough/high idle. Is this probable?