At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.
How do you test the crank and cam sensors on 02 town & country 3.3 l engine? mine cranks no start has fuel & spark. the last few weeks it stumble occassionally at idle. Thanks
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
manual trans car, easy one, 5speed.
WHEN DID IT LAST RUN GOOD, LAST YEAR OR DECADE WHAT FUEL DOES IT BURN? AND IS FUEL OLD?
I can't guess country yet (wires vary by that, colors and laws)
noT turn over means , engine cranks ok(starter turns) and crank shaft turns, but will not start nor stay running or does start but stalls fast.
well that has over 50 causeS!. (in details)
cranks fast but he engine will not START.
NO ENGINE told and is a pure engine question.
a gen 1 pathfinder, no country told
I came new world wide with this wiki list of engine nobody can guess.
IF ENGINE IS GOOD. (I'd never assume it was I do tests to learn that)
if gasoline (petrol) check spark on all spark plugs..
if spark timing is off, the cam belt slipped (a 100k mile service point)
no car with 29 year old spark parts will run, impossible that.
if spark is good and test spray fuel works we attack fuel
1,2,3 good engine, good spark work fuel last.
a fuel pressure test is next.
also this old.
EGR valve stuck open
and or IAC valve stuck closed, try cranking with 5% foot throttle added.
I saw what you replaced. What testing have done? Generally, if it cranks good but won't start, have a helper crank it while you check for spark at the plugs, if spark everywhere, use a gage and check proper fuel pressure. Also, check fuel injector pulse. If your missing everything, I'd check for rpm signal. A lot of Chrysler makes and models, the computer has to see proper signal from cam and crank sensors or it won't ground the asd relay. The asd relay supplies voltage to several systems, including ignition coil and fuel injectors. Engine cranking, do you have primary voltage to those two components? Use a test light. Any applicable trouble codes?
the coil does not crank the engine , the starter does that, sorry.
(if you ever had to hand or foot crank and engine , youd under stand that. (like motor cycles or boat engines, or per 30s cars.)
in fact will crank all day with no spark parts on car..
x2, the scan tool does tell you why there is NO STARTS, CRANKS OK. The pcm can detect, one missfire in 10 cmp;ckp signals.
CRANK FOR 5 SECONDS
release, key
scan tool has DTC errors?, read the believe them.
no engine stated of 4 or more,
U checked everything but spark,
why, check spark at all cylinders, all most fire or the engine will not run or stall.
That test be first, if not starting (AFTER SCAN TEST)
IF NO spark fuses are next , not last.
lets do no start fails tests. (cranks perfectly 200 to 300 rpm)
: check fuses
key on, CEL lamp must glow, if not , ECU fuse blown.
crank with scan tool , see P03xx DTC errors, see RPM dead.?
check for spark? got spark x4 or times number of cylinders?
got spark try test fuel now, runs for 3 seconds?
yes, runs on test fuel now means lost fueling
no, dont run on test fuel, means, 1 to 5 done wrong above or engine compression bad.
bad fueling, huge number of tests. check fuel pressure now.
2000 Dodge Stratus. with Automatic transmission?
No engine size stated, so all answers are GENERIC.
will it crank, if it dont crank over fast post that.
no engine starts, unless cranked or with MT/ push started or gravity started.
i think "wants" means it cranks , over, ROBUSTLY.
i have a text file here for no starts. (cranks ok)
quote(me):"
Gas engines: (Otto Cycle)
the classic, engine has good spec.1-compression, then 2-good spark and last 3- good fueling still works.
123, simple,called basics.
I will call the ECU a PCM.(modern named) and USA spec, cars only.
Powertrain control Module (the magic device, that runs fuel injection and spark)
Check all fuses using any Ohmmeter (resistance) or any DMM with one inside. Zero Ohms or less than 1 is a good fuse.
The PCM can not run any engine, if 12vdc electrical power is missing on any car. Use the same meter to be sure the PCM has full 12.6vdc power from the battery, key on.
The CIG lighter port is a convenient test point. just key on 12.6vdc
If the IMMoblizer lamp glows, the engine will not start.
If the security lamp glows, on many cars the car will not start. (read the operators guide it explains all this in the section "how to start your engine"
The CEL lamp must glow key on, if not?, that means the PCM is DEAD.
There are 3 or more PCM fuses, and are already tested.
On 1996 and newer cars (USA) if the scan tool can not communicate, then the ECU is dead, (or fuses blown )
OK , key on CEL out , IMMO out , Security out.
Crank for 5 seconds, with scan tool attached, see DTC's now? BINGO.!
All PCMs can report bad sensors cranking. Even the old OBD1 cars.
SPaRK, if there are no DTC errors, there might spark now on, all cylinders.
check them all ,because, 1 bad and all bad are two different causes.
If spark is 100% dead , many cars you can remove the distributor cap to see of cam spins, if not?,the cam belt snapped. or on some, with no actual distributor, you can look down inside the oil filler cap hole and see the cam spin.(cranking)
if the CAM stops spinning,. ANY ! PCM WILL report that. (CMP dead) cmp = cam sensor.
NEXT:
I check for spark and if it's good on all cylinders, I then check spark timing, ) see if timing is way off?, that means the cam belt or (hard to believe; chain slipped) fix that now. (a strobe light is $20 today)
strobe = automotive spark timing light.
SPARK GOOD, now (last )
NEXT FUELING:
As Scotty shows, he then uses test fuel; if car runs good, for 3 seconds, then you have all things good, so far and , just bad (dead) fueling if engine runs only 3 seconds, on test fuel.
SAY NO fuel injected?
check fuel pressure is over 30PSI, (see fsm for spec) and use a NOID light to see if the PCM is sending injecton pulses.
You can listen to injectors with a stethoscope, but is hard to hear cranking. (i have special tool for that)
there are up to 6 tests for the fuel pressure, including leakdown, shunt test and balance.
OK it's flooding. (spark tips soaked in fuel)
Please be aware that leaking injectors (1 or or more) can cause no starts and is flooding , if I suspect it (black cloud at tail pipe end) I do the injector leakdown and balance test ,now)
To clear flooding, crank with the throttle wide open,this trick cuts fuel.
if it still foods you can pull the fuel pump relay to kill the pump , the crank it dry.
Flooding is a whole set of tests. to find true cause.
Too high fuel presssure, say 65 PSI or more?
ECT stuck at -30F degrees?
injectors leaking.
no startup air supply , ISC stuck closed?
end, (ask for help for any of these possible paths)"
Could be crank sensor , ignition module and i wouldn't rule out the PCM . But before you start replacing parts test these componets . If you don't have diagnostic skills or a lab scope i suggest you take to a qualified repair shop that does . Hall effect cam crank sensor operation and testing Part 1 an SD Premium...
There is no simple answer, there are to many variables.
If you have access to a scan tool, pulling the codes should help. Without them its back to old school hunt and peck method.
At this point we need to narrow down the problem. You need to test for spark.
Tag and disconnect the spark plug wires from the spark plugs.
Remove the spark plugs and install the spark plug wires to each spark plug.
Ground (do not hold spark plug) the spark plug; check if spark occurs while engine is being cranked.
Crank the engine for no more than 2 seconds at a time to prevent flooding the engine with gasoline.
If you have spark, You will want to make sure you have
fuel injector pulse, along with fuel pressure. If you have spark
..simply spray some starting fluid in through the air filter
and hold the gas pedal to the floor and crank it over while spraying.
If it fires up, you know it is fuel related( fuel pump, regulator, or
ECM if no injector pulse) .
If you have no spark then look at ignition coil connection and trace through to the distributor( if equipped ). The crank shaft sensor has a tendency to fail on these as well.
This should give you a few things to test and check to start you on your way to narrowing it down.
If you have no spark then look at ignition coil connection for power and trace through to the distributor( if equipped ). If it is DIS( no distributor). It may be the Crank sensor or the ECU. The crank shaft sensor has a tendency to fail on these as well.
The ECU uses the signal sent from the Crank sensor to trigger the spark and fuel injectors. ( make certain you have checked all fuses)
×