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Discussion Starter #1
OK I know a little about cars. So far sportages have produced the most problems. This thing STILL missfires. Brand new plugs wires coils coil boots I've dbl checked for arching..none. MAF and IAC cleaned and operating. Vacuum is tight and secure I've checked and replaced hoses. New PVC valve and gromet. Fuel filter new in last year. No problems with battle or alt. Main problem is random missfire at idle and at higher rpm? Maybe an o2 sensor and if it was would it be the upper or lower? Advice on how to check them with a volt meter.. ect? I love advice!
 

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re: checking voltages, kiatechinfo website (see my sig.) for values,

but would recommend using a live data scanner to view/confirm o2 sensor range and switching..

re: misfires, if you are confident that illegal air, spark, and fuel are not the cause, go further back - check and confirm mechanical timing, check and confirm the exhaust manifold is intact (no cracks/leaks), check and confirm the pre-Cat converter below the exhaust manifold is intact / no exhaust restriction..

re:Spark - if the lead from the back of the motor to the coil packs is at all suspect ( wear on wiring or cracks on connectors ) - replace that lead.

As a sanity check after mechanical timing / manifold checks, I would perform a compression test to verify values are good / as expected,

(Why compression test after physical verification of timing? Your timing may be off by (1) or (2) teeth on the timing belt, and your compression numbers will be lower, but acceptable, however your Sporty will still be dumping extra fuel while running / affecting the pre-Cat.)


If basic mechanical timing is confirmed good, and no issues with exhaust manifold / pre-Cat. converter / exhaust restriction, compression is good,

would recommend checking fuel system using a fuel pressure gauge next (Operating pressure / return & FPR / pressure hold..)

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But you know your Sporty better than I do, if you feel it is electrical-related, highly recommend cleaning up those ground points, including the fuel pump ground ring: All tests at kiatechinfo assume good power to motor and frame, relays in proper working order, and confirmed basic mechanical timing..

Regards,
GottaCruise
 

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2-2000 1-2006ALL SPORTAGES also 96 dodge van to transport dogs and 84 gmc snow plow.
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Have you cleaned all your grounds, from neg. to batt. tray batt. tray to to mounting ( with batt. removed ). There is a short coil supply wire, two into one, in the back of engine.The platic connectors get brittle an crack or corrode . replacement wire is available . check vacuum 19 to 22 normal with a steady needle.
Check mounting gasket on iac rips. Cleam map sensor with map sensor cleaner or electrical cleaner only.
https://www.kiatechinfo.com/TechnicalInformation/Viewer/default.asp?title_num=8&menu_type=1_1 kiateckinfo. works with internet explorer only . shows you how to test ox. sensor. Post cel #'s . chief
 

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2-2000 1-2006ALL SPORTAGES also 96 dodge van to transport dogs and 84 gmc snow plow.
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Sorry Cruise for over posting something about brilliant mines.
chief
 

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That's cool Chief - I thoroughly agree verifying basic electrical is an -excellent- starting point, was just a little quicker on the 'send' button.. :)

* My time is very limited next several days, any help you can offer matt is most appreciated,

Best Regards,
GottaCruise
 

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2001 Kia Sportage, 2003 Toyota Sienna, (1995 Saturn SL1 - gone, was a great car though)
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Maybe one of the expert's can chime in on this...

From my experince the past few years with fuel injected systems, is the engine coolant temp sensor is often an overlooked componenent and plays a huge part in calculations the ECM makes, particularly when it comes to the timing advance. If the temp sensor produced a value that was in range for self testing, but totally wrong for the chemestry might it then produce a backfire?

Just a thought? It could be an easy thing to check and rule out.
 

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Discussion Starter #8
Thanks for the advice I'm going to start by checking grounds and make sure the timing is correct. I cleaned the maf sensor the iac valve and they are sealed tight. I can hear a squeeky pully was assuming it could be the timing tensioner. Maybe jumped a tooth or something. Random question- if you remove your oil cap while running should the motor sound different? This is another reason I'm kind of leaning towards the timing.. thanks for the advice so far! And when I find time I'll fill my profile info. I'm in Ohio!!!
 

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Hi Aaiiee,

It can and will - the engine coolant temp sensor (ECT), air intake temp sensor (IAT), the primary O2 sensor (B1S1), the MAF sensor, and the throttle position sensor (TPS) are all used in calculating air/fuel mix ratio (injection) when operating in closed-loop mode,

The Cam position sensor and Crank position sensor advise the ECM "when" to initiate (fuel) injection & firing (spark) - signals from these sensors allow the ECM to adjust (dynamic) timing on the motor when starting/running,

"Static" timing is the physical alignment (lining-up) of the (Intake), (Exhaust), and (Crank) pulleys to cylinder #1 top-dead-center (TDC) -- to ensure the physical valve-train and cylinders are in proper alignment when operating,

The ECM also accepts other sensor data, Knock sensor, Speed sensor - knock sensor is used to advance/retard timing to prevent engine knock, speed sensor is used for Transmission shift points: I dunno if speed sensor is used in ECM calcs on the Sporty..

"Popping" at the intake side may indicate illegal air entering after the MAF sensor - the PCV hose, and intake manifold for missing hoses/caps is one area to check,

"Backfiring" at the exhaust side may indicate ignition/spark or fuel issues - Q/A'ing the ignition components, static timing, and exhaust for restriction may be areas to check,
as a starting point before fuel testing..

*These are just -general- recommendations: I am not a certified ASE tech, just a 'shade tree' auto repair enthusiast,

always recommend seeking professional advice and assistance as needed,

Regards,
GottaCruise
 

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Discussion Starter #10
Thanks for advice I'll look into some of them and reply back. m lost for words. It missfires worse cold then hot. And at stops and when u first try to accelerate. Then it kicks n goes.
 

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You can test the temp sensor with a ohm meter. its the one on the drivers side two wire connection. values are listed & kiateckinfo.
When was the timing belt changed an how many miles on it now ?
You can check the timing with a timing light but can't adjust it. or a scanner.
Just a couple more quick checks.
chief
 

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Discussion Starter #12
I never checked temp sensor.. and its almost 140k I've never changed the timing ever. So that means not in the last 60k miles. Will temp sensor make it idle like crap missfire and stutter at take off?
 
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