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Discussion Starter #1
So when I am at lights or stopped and my fans turn on my rpms flutuate between 1000 and 200 or so and every once in a while my batt light flashes. The cars done this since I have got it although I found a disconneted vac line and it,got rid of the batt light issue for a while but now its back. When the fans turn on my lights dim for a a second also, but the thing is I had the charging system checked and the altetnator and batt came up as fine. What is the issue? Any help appreciated, and I cant find any loose vac lines so cant see it being that.
 

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The batt light is telling you you have charging issues.
Put the odometer in test mode and see what the car is seeing for voltage.
Should be (bXX.X)
 

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Keep looking for vac line issues, PCV & hose ever been done?, If idle varies with load (fans turning on) the IAC might not be working up to snuff....

When idle gets ridiculously low, batt. light WOULD come on, since the engine isn't spinning fast enough to produce appreciable power at the alternator....

And B4 getting TOO deep into arcane diagnostics, the basic questions are 1. engine basic mechanical condition (ever check compression?) 2. basic maintenance (fuel filter, spark plugs, wires, air filter, PCV & hose) 3. longer term maint. ( timing belt, check base of coil for cracking - removal needed - a "focus specific" check ) 4. the "obvious" (fluids topped up & reasonably fresh, no leaks or strange noises, good fuel at least half full... etc.)

Luck!
 

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Discussion Starter #4
How do u put.the odo in test mode? And I jyst replace the plugs with denso iridiunsabout 10 miles ago and new wires and.what line Is the iac and where is it located? I just bought the car about 5 months ago so idk when timing belt was replaced, but it has had a new oil change at.about 1000 mi after I got it
 

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"sticky' at the top will give a full rundown on the "test mode" for the odometer.

Given the model year, I'm SURE there are enough miles on the car - and FOR SURE enough years to need a timing belt as a basic maint. preventative measure. Unless yo check it and it looks BRAND NEW start saving for a belt, tensioner & idler pulley (avail. as a kit), and to save doing things twice many recommend the full maint. on serpentine (belt, tensioner, idler pulley) & even water pump as well.

None of this is urgent, unless something looks bad right now - it's just needed to avoid future issues when you can get around to it.

Fuel filter IS an important piece to make SURE it's been replaced recently, since MANY issues result from one that's gone too long without replacement.

Factory plugs, with the gap checked, give the best results for a daily driver both in operation & longevity. Wrong gap in particular, and non-stock brands, sometimes cause issues as noted in practical experience from many posters on this site.

The IAC isn't a "line", it's an electrically controlled valve that looks like a cylinder attached to the throttle body. Search long enough & you'll find a picture somewhere here - sorry I can't give a direct reference to the posting for that...

Did you check the old plugs for condition when removed? THAT is the best diagnostic for engine running condition over time... Deposits, color, all important! There are many resources with pictures for spark plug condition diagnostics, both on-line & in printed manuals. A glance at a diagnostic chart for plugs will teach you a LOT about what's going on in the engine...

Keep checking, get back with more info. & all the regulars here will help you work through any & all issues!

Luck!
 

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Rusty isn't an issue, the question is How the insulators & electrodes looked!
 

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Ya Gotta remember,at the other end of the "net", we have NO clue as to what YOU are seeing.... OR what your knowledge & experience level is....

"FINE" to one person, might be "totally [:)][:)][:)][:)][:)][:)] up" to another... (grin)

SO, some detail would be nice - since we can't see it from here.....

Thanks!
 

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"fluctuating" isn't good, it SHOULD be stable......
 

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Don't "jump the gun" - aS ONE OF OUR major REGULARS changed his name to, "WHYNOTTHINKWHYNOT...

Deal with ONE issue at a time, and THINK B4 spending that hard won cash....

All depends on your meter, 14.3 sounds good, "jumping" between that and 13.9 doesn't - BUT some meters are VERY sensitive, and "Jump" a lot...

if you DON'T have "experience" with the meter, so you DON'T know how it reacts "normally" you are just guessing without adequate information - and THAT leads to spending money you DON'T need to....

Checking & cleaning (yup, that requires disassembly) of ALL battery connections, ground connections, alternator connections - is the FIRST step - cause it doesn't COST anything but time....


THEN see what the voltage does at idle....

THEN it should be stable.... You MIGHT see spikes as things turn on & off, but the general result SHOULD be a stable voltage in the 14 plus range....

luck!
 
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