Tip & How-To about Ford Focus

Modern cars are not hard to troubleshoot

All cars; new or, old. follow the same laws of physics.
fuel+air+electricity=running engine.
So; first we look for fuel: there are two ways to do this: while turning the key to run
lean out of the driver's seat and, listen for a short 2-3 sec. buzz; this will be the electric
in-tank fuel pump starting up, holding pressure and, shutting off to wait for a demand for fuel
if you hear this the fuel delivery system is good.
Next; we look for; spark (electricity) the only safe way to troubleshoot modern computerized
ignitions is with a inductive timing light; hook the timing light power lead clips to:
the car's battery: red to the positive post and, black to the negative post; then: take
the inductive clamp and, hook it around a spark plug wire; any wire will do:
crank the engine and, count between the flashes a four cylinder will flash either every time if the clamp is on a main lead or, once every four times the engine rotates again. of course the count is: six for a six cylinder; eight for an eight etc.
No spark? ignition has failed. Next: air in the intake of your car is a small flap attached to a switch; open the intake and, crank the engine while spraying starter fluid (ether) into the intake engine starts then dies; fuel filter failure; no start: flap switch failure (no fancy names here)
engine runs replace air filter. of course this doesn't cover everything sometimes even we
mechanics get stumped; but, this should at least prevent you from not spending a fortune to
fix your car

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2 Answers

96 olds lss had fuel pump replaced wont stay started long sputter spits ect.

You better find a different mechanic . Before calling a bad fuel pump ,did he do fuel pressure test ? Did he test the electrical circuit ? Did he check mass air flow sensor ,injectors , fuel regulator , engine senors ? How many miles on the vehicle , is the engine in good shape ? Timing chain ?

Aug 05, 2016 | Cars & Trucks

3 Answers

2000 Jeep Grand Cherokee Laredo 4.7 liter code reads p0307 turn the car off when I turn it back on started misfiring and sputtering and wont stay started now help

code p 0307 is misfiring on no 7 cylinder ====causes --- engine mechanical fault ---wiring---ignition/ fuel system--injector --ECT/MAF sensor---ECM
look for low fuel pressure or ignition control module

May 31, 2016 | 2000 Jeep Grand Cherokee Laredo

1 Answer

bad body throttle

old posts .
if it cranks all engine stall for the following reason.
(physics) in the proper order.
1: engine bad. (or cant breath) (compression loss huge 1 or more cylinders.
2: this engine 1.0L or 1.3 runs on GAS, and spark is next , no spark running end. (slow or fast, and is called misfiring)
3: bad fuel, (too much flooding its called or too little bogging and stalls)

1,2,3, its one of those 3 things
there 3 exceptions (kinda)
a: battery power ended, 12v became 8v and engine stalls, actually EFI goes (OFFLINE) when no power. to run it.
b: EGR stuck open. very common, make all the above useless when stuck open.

c: idle air, the engine need air to breath or it floods.
there are 2 parts related to this fact, IAC valves if many times. or ISC valves, that meter air hot or cold engine.
(thermal air valve or electric or both)
if they stick closed, no air now , engine stalls , unless you right hot foot the throttle pedal and save the stall., if that is super easy , you lost air !

the number 1 reason for stalls in not getting tuneup.
Are your spark plugs in car , antique?
going for the 10 year record on spark plugs, or spark wires.
then FILTERs.
to solve this riddle, the shop uses TOOLS, those tools.
Gauges , meters, scanners and scopes.
Make the job easy and fast.
why not ask a shop just to diagnose car. (be wise to tune up first and not have them prove to you with hours of labor proving, gee,
all these parts here, are useless. (aka. basic service points parts)

Apr 11, 2014 | 1997 Geo Metro

2 Answers

starts but shuts off then wont start

sounds like a immobilizer issue to me.

Feb 28, 2014 | 1988 Isuzu Trooper 2 Door

1 Answer

I have a 92 dodge stealth rt car will not start unless I spray starting fluid into the throttle body.I had new fuel pump installed due to old pump had no pressure.Car will still not start even with new pump also put in new fuel pressure regulator. Car has good compression and car has only 56000 miles.Can anybody tell me what else I can check.Can the knock sensor also cause this problem.Thanks in advance I hope somebody can help me.

Did you check fuel pump electrical circuit ? Look at a wiring diagram to see what all is involved in making the fuel pump work. No , the knock sensor can't cause this ! Do you know how to do automotive electrical circuit testing using a DVOM - digital volt ohm meter ? How to read an use a wiring diagram to pin point areas for testing in a electrical circuit ! What do you think makes that fuel pump work ? AIR !!!! Looking at a wiring diagram I see a fuel pump relay that gets B+ voltage from the engine control relay. The engine computer energizes both, relays .There is a fuel pump resistor inline before the fuel pump.
Free wiring diagrams here http://www.bbbind.com/free_tsb.html Enter vehicle info. year , make , model and engine size. Under system click on engine then under subsystem click fuel controls ! Click the search button then the second blue link . The second diagram down shows the fuel pump electrical circuit .
Watch this videos from youtube .
Basic Electricity for Service Techs Ohm law Current Flow Opens Shorts
Electric Testing Techniques You Need to Know

How to Use Multimeter to Troubleshoot Common Problems

Jul 06, 2017 | Dodge Stealth Cars & Trucks

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