Posted by jimg.allentown on June 05, 2016 at 19:30:31 from (108.2.196.109):
In Reply to: Any GM Mechanics? posted by Steve@Advance on June 04, 2016 at 12:07:12:
MAP sensor is a mixture control device. It "measures" the amount of air going into the engine based on the vacuum reading. Sensitive, but less accurate than a MAF sensor. MAF sensor measures the rate of air entering the engine based on the current it takes to keep the "hot wire" up to a specific temperature. Much m0ore accurate, and replaces the MAP sensor. You may still have a BARO sensor.
Your symptom seems to point more to a TP sensor or a gas pedal sensor. A scanner may give you some indication of a problem, but more likely you are getting a "dirty" signal. That is, the signal from the sensor is not a good clean DC voltage signal. The only way to verify that would be with a scope. Also, since you have a "fly by wire" throttle control, you have a sensor in the gas pedal as well as one on the throttle body.
Also, keep in mind that a Mass Air Flow sensor will NOT set a code unless it is a major failure of that sensor. It can go "out of calibration" and cause the mixture to get too rich or too lean.
Timing is another potential problem. Timing is continually varied by the PCM, and a CKP or CMP giving a "dirty" signal can also be a source of trouble. Maybe check that the connectors are clean and tight on them.
As a BTW, by law, emission control systems are covered by a 5 year/50,000 mile warranty. The entire engine control system from the PCM to the lowliest sensor are part of that emission system. A trip to the dealer with your complaint may be in order. They have diagnostic equipment that dwarfs anything that either a mechanic or a third party shop may have.
Upload one or more videos to your post. Photo filesizes should be less than 300K and Videos, less than 2MB. Formats allowed are gif, jpg, png, ogg, mp4, mov, and avi. Be sure to use filenames without spaces or special characters, and filetypes of 3 digits lower case.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Restoration Story: Fordson Major - by Anthony West. George bought his Fordson Major from a an implement sale about 18 years ago for £200.00 (UK). There is no known history regarding its origins or what service it had done, but the following work was undertaken alone to bring it up to show standard. From the engine number, it was found that this Major was produced late 1946. It was almost complete but had various parts that would definitely need replacing.
... [Read Article]
Latest Ad:
1964 I-H 140 tractor with cultivators and sidedresser. Starts and runs good. Asking 2650. CALL RON AT 502-319-1952
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
