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The lead technician
"No start no spark @ plugs replaced crank sensor cam sensor still no start. Should i perform a compressio
Can you help him out?
Does the "theft" light on the dash flash when you try to start the car? Have you checked for codes? Are the injectors firing? Why did you replace the cam/crank sensors? What test(s) have you already performed and what were the results? Did the car die on the customer while driving, or just all of a sudden decided it didn't want to start? What work has been performed recently?
Successful diagnosis of any drivability problem depends on how well you do your homework before replacing any parts. The more you know up front about the problem, the easier it is to find the root cause.
You should be able to get an idea of compression while cranking. Does it crank over normally? Too slow? Too fast? If you've already identified that it has no spark, next check for injector firing. That should provide some initial direction.
Let us know when you have more info...and we'll do all we can to help!
HAs a clutch been done recently? if so make sure the flywheel has not been machined, a flywheel to thin will cause the cam sensor not to register. Also check the flywheel counter sensor mounted on the front of the engine near where the bell housing and engine block connects, if broken the ecm will not know where to start the coil firing sequence. also check the two ground wires on the intake manifold between injector # 2 and #4 if loose the injector harness will not be grounded and lastly check the wires at the crank postiton sensor near the balancer pulley, if the wires are oil covered clean them and make sure they are not broke, also check the cam sensor wiring on the right side of the engine near the motor mount and water pump acess cover.. 1 last thing make sure the rubber in the balancer pulley is not broken the pulley is 2 pieces if it breaks the inside of the balancer will move and the sensing ring for the crank sensor won't move. hope this helps
Of all the replies I have read... I can't agree more and couldn't have said it any better from any one of the replies.
Car repair isn't "throw a dart at a wall chart of parts and change whatever it lands on... sounds to me like; "OH, no spark... heck, lets change the crank sensor" ... a dah ! ! You blew your cover buddy... it's offical... you don't have a clue what your doing" changing parts for the sake of trial and error and not knowing any scan results or whether that paticular part even controls what you think it does (crank sensors, cam sensors can control either spark or fuel just for the record... even after all my years I still have to check the books to see which one does which on each different model... think about this, without research on the vehicles systems ie., theft, ignition, fuel etc.. .your just being idiotic...
If you don't have a clue what your doing... find something else to do. Professional technicians in the trade don't change parts and hope for a repair .. we study and work at our trade each and every day to learn the varity of systems that are out there. ...
You might as well replace the kitchen faucet because the front door won't unlock... makes about as much sense. And the real problem is CENTS... how much money do you spend on swapping parts before you give up... I hear it all the time when other shops bring a no start to my shop... ask some wrench rocket what's wrong with the car and the first thing out of their pie hole is "I changed this, I changed that, and I changed those too. Yep, now I know what's wrong with the car... there's a box of wrenches and no brain attached. Wouldn't be the first time I've seen a car with hundreds of dollars of parts thrown at it and the whole problem is a fuse or bad section of wiring.
I would at least like to think that the tech on the other end of this has at least a few tools in his box... sounds to me like he needs to find a few more before tackling another customers car or asking questions that are way to far off the diagnostic path to be worthy of an answer.
I'd like to help ya... but I think Pete said it best.... To many unanswered questions and too many things that weren't descibed well enough to make any sense of the causes.
Thinking back to 1967, I can imagine that was before most of you were working, or even before some of you were even born. Well back in 1967 I was in a military school studying diesel engine maintenance and repairs. The service manual on a Cummins 855 engine was about 1/2" thick. That manual covered at least ten years of this engine. I can remember one of the instructors standing in front of the classroom and telling his students about using service manuals. He said over and over again over a period of 8 weeks,,,, when asked a question about an engine problem, the correct answer is, "let me go look up that information". If that were true back in 1967, how much more true is that today? I realize that is not proper english, but I think it does make the point, that technicians need to be well versed in the use of their service information. They need to use it and become familiar with the information, so that they can locate their needed information quickly and accurately. Most times the reason that we cannot find what we need is because we do not look in the right place. I find myself, that the reason I look in the wrong place is because I am not familiar enough with what I am doing. There is always room for improvemtnt.
At a quick glance I see 3 or more TSB`s on the subject.If