1994 Ford Ranger Repair Question
Topics covered: Compression, Engine, Rough idle.
Mileage: 13,100 miles.
Mileage: 13,100 miles.
Asked on September 19, 2012
Code 40?
Vehicle is 1994 Ranger, 3.0L, 2wd, 49 States emission, 131,000miles.
Failed California Smog at 15MPH on all gases(HC 172:CO .73:NO 1354.)Fine at all other tested speeds.
Diag from shop indicates Code 40(?; I am unable to find this code.) Repair recommended is new cats(both) and reman engine install(low compression cylinders #4-100 and #5-130.)to correct rough idle. No recommend of fuel filter, injector clean, throttle body or MAF clean. My question is: what should be the cylinder compression reading and what is code 40?
Any questions, comments, or recommendations will be appreciated.
Failed California Smog at 15MPH on all gases(HC 172:CO .73:NO 1354.)Fine at all other tested speeds.
Diag from shop indicates Code 40(?; I am unable to find this code.) Repair recommended is new cats(both) and reman engine install(low compression cylinders #4-100 and #5-130.)to correct rough idle. No recommend of fuel filter, injector clean, throttle body or MAF clean. My question is: what should be the cylinder compression reading and what is code 40?
Any questions, comments, or recommendations will be appreciated.
Asked by psh1Answer
Replied on September 19, 2012
cyl compression should be within 20% of each one which you are close to the 20%but not there yet. all that code 40 is is a cylinder balance code and says #4 is reading electonically off. the low cylinder can be a valve starting to burn or go bad, a vacuum leak or a larger internal problem.check fuel pressure as that can give a rough idle as well as a vacuum leak. with the engine running it should be 28-45 psi
