High Idle? ERB?

i have posted before about this problem. my friends brother has a 89 4.0L straight6 H.O.. i had recently taken the car to school where i have this auto class and did a scan check with a SnapOn scanner. this is the only way because none of the auto part stores scan OBD1 anymore. it would not let me see if their is any trouble codes. so i asked the teacher and we went on to the All Data website and looked up the VIN number to see some other stuff about the VIN number. we get to the 4th one and it says it should be a H,C,O,or N. but the 4th one is a F. so we are confused and the teacher calls the dealership to find out more info. they said something about a ERB engine. waht does ERB mean? anyone know? and is their possibly 2 O2 sensors on exhaust? because engine floods out easly and we have replaces one on manifold. is thier one after cat. we see no wire cause exhaust got ripped off in back? their was a recal on O2 and was not claimed by previous owner so we are going to fix the exhaust and take it in.


ANY HELP WOULD BE GREATLY APPRECIATED!

Well to start, your friend has the regular 4.0, the ho didn't come out till early 90's. Your question about the 02"s, there is only one, its on the bottom section of the manifold. So your problem is flooding out? Tis could be a couple things, check your fuel pressure, it should be about 30-34 psi w/ regulator connected and about 40 psi with it disconnected. Also there are a couple threads about replacing the stock injectors with # 19"s out of a 5.0 mustang engine. It will cost about $250, but its worth it. I did it to mine and it runs very well. I say this cause you could have a couple leaking, flooding the cylinders out. Look at you oil too, is it thinned out and smell like fuel?

High idle, have you checked your Idle step motor on the T-body? This controls your engines idle speed by a pintel opening and allowing air into the t-body. THere could be carbon deposits on the pintel. Remove the t-body and clean it real good, becareful not to get the electrical sensors soaked in cleaner.

He had replaced both the oxygen sensor and that one on the throttle body. he said when he replaced the one on the throttle body it ran fine after he plugged the sensor in then after he shut car off and turned it back on it went back into high idle. the o2 sensor does have a relay on it. so we are going to check that first.

forget the 02 sensor. it is strictly an input to the pcm on fuel/ air management. Your high idle is caused by either a sticking Idle step motor or crud in the t-body where the pintle of the ISM recesses to restrict air flow.Thus controlling your idle speed. Also make sure that your throttle cable isn't binding up. Simple things will get you every time. If you have a chiltons or a haynes, check to see is you are getting the proper Voltage to the ISM. You may have a PCM issue.
Oh, again, you have only ONE o2 sensor!