How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Amedee Your Own Question

Amedee
Amedee, ASE Master Tech
Category: Car
Satisfied Customers: 21823
Experience:  ASE Master Tech advanced level specialist. Wisconsin certified emissions state inspector
Type Your Car Question Here...
Amedee is online now
A new question is answered every 9 seconds

no spark on 4 cylinders cam and crank sensor signal present at pcm

Customer Question

no spark on 4 cylinders cam and crank sensor signal present at pcm the coil drivers one pulses fine one sends constant signal and one sends no signal at all
Submitted: 3 years ago.
Category: Car
Expert:  Amedee replied 3 years ago.
Hi Customer. Thank you for asking your question on JustAnswer. The other Experts and I are working on your answer. By the way, it would help us to know:

-What year is your Car?
-What make and model is your Car?
-How many miles are on your Car?
-What type of engine is in your Car?
-What have you already tried?

Thank you again for trusting us with your problem. Please reply as soon as possible so that we can finish answering your question.
Customer: replied 3 years ago.
sorry 1994 chrysler lhs 3.5l ive tried new crank and cam sensor plugs wires and coil pack
Expert:  Amedee replied 3 years ago.
Ok.. chances are you motor is out of time. You will need to pull the front timing cover and check the timing marks. I have a feeling you will find your problem.
Customer: replied 3 years ago.
sorry ive done that also all timing marks are lined up
Expert:  Amedee replied 3 years ago.
Then if the cam ansd crank signals back to the PCM are ok, then the only thing left is a bad PCM
Customer: replied 3 years ago.

is there any grounds that might be bad causing the problem or something stupid stuff like that

 

Expert:  Amedee replied 3 years ago.
Sure.. the PCM could have bad grounds... but if it is firing the other cylinders... then they should be ok.
Customer: replied 3 years ago.
could one of the other sensors cause a no start situation on that car
Expert:  Amedee replied 3 years ago.
The cam and the crank signals are the only two signals the computer needs to fire the produce spark.
Customer: replied 3 years ago.
yeah but if a oxygen sensor is faulted out will it keepin the engine from running on this car or any other sensor trip a protection mode
Expert:  Amedee replied 3 years ago.
NO... none of them will cause this no spark condition like you are having besides the cam and crank sensors and signals back to the computer.
Customer: replied 3 years ago.

so you are 100 percent on the pcm

 

Expert:  Amedee replied 3 years ago.
No... I am confident that the cam nd crank are not in sync with each other.

If they are, then chances are the reluctor on the cam or crank is going to be damaged or an issue causing this problem.
Customer: replied 3 years ago.

so what should i do next

Customer: replied 3 years ago.

i have checked the ring on the fly wheel and it is fine

Expert:  Amedee replied 3 years ago.
You need to scope the cam and crank sensors and verify that they are in sync with each other. You will need ot compare this scope pattern to known good pattern for this engine. If and only if this checks out ok, then replace the PCM.
Expert:  Amedee replied 3 years ago.
I realize that this answer may not be entirely to your liking, and I regret being the bearer of information that you really don’t want to hear. But it would be unfair to you and unprofessional of me were I to provide you with anything less than truthful and honest information. I hope you understand

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
< Last | Next >
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles Walnut Creek, CA
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue Charleston, WV
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim Castleberry, FL
  • Excellent reply, and also very quick. Really sounds like the Expert knows what he is talking about. I will be back to use your service when I need more help with my RV. Dutch USA
 
 
 

Meet The Experts:

 
 
 
  • Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
< Last | Next >
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka-Moose)'s Avatar

    Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
  • http://ww2.justanswer.com/uploads/TE/TedG/2012-6-15_14759_avaLarge.64x64.jpg Ted G.'s Avatar

    Ted G.

    ASE Certified Technician

    Satisfied Customers:

    1596
    20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness
  • http://ww2.justanswer.com/uploads/joecamel90/2008-11-13_03615_head_shot.jpg George H.'s Avatar

    George H.

    ASE Certified Technician

    Satisfied Customers:

    1311
    ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist
  • http://ww2.justanswer.com/uploads/AM/amedee/2013-10-24_23656_Amedee1.64x64.jpg Amedee's Avatar

    Amedee

    ASE Master Tech

    Satisfied Customers:

    2367
    ASE Master Tech advanced level specialist
  • http://ww2.justanswer.com/uploads/SU/supermechanic/2013-8-23_03546_500.64x64.jpg Jerry's Avatar

    Jerry

    Master Mechanic

    Satisfied Customers:

    1906
    ASE master, 30+ years. All makes and models. Trouble shooter, shop forman, service manager
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar

    Richard

    ASE Certified Technician

    Satisfied Customers:

    942
    12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes
  • http://ww2.justanswer.com/uploads/ST/Steve7654/2012-6-5_215929_japic800x660.64x64.jpg Steve's Avatar

    Steve

    Auto Service Technician

    Satisfied Customers:

    1980
    25+ yrs experience as a professional working technician; ASE L1 master technician