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2002 Rio Cinco 1.5
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Discussion Starter · #1 ·
I need 2nd opinions please!

Rio Cinco 2002 with 154,000 miles on it.
Original Timing belt replaced at 93,000 miles.

It now has erratic/choppy acceleration, also an occasional misfire/hiccup w/AC on both at idle and at high speeds.
Also early morning cold crank is now difficult even with new starter.

It all started a year ago:
Car stalled at stop sign. Mechanic said MAF Mass Air Flow code > check vacuum hoses. A hose had fallen off under the air filter box.
Installed new plugs and new plug-wire set
Replaced valve cover gasket with KIA gasket.

code reset but still runs rough. 3 days pass.

Code tripped again. Mass Air Flow. All vacuum hoses under air-cleaner box have been replaced with Kia hoses.
New in-line fuel filter installed.
Intake-air-sensor replaced.
Re-manufactured MAF sensor installed and it runs better for about 6 months and begins to run rough again.

Starter fails and had it replaced.

Replaced MAF sensor again and it got even worse. Error code MAF PO172. running +20% rich

Told tech it had a new MAF so they replaced the upper Oxygen sensor.
Still runs rough. No codes however.

Went to Kia Dealer and they checked plugs, plug wires, no oil in spark plug wells. They suggested taking the timing cover off to check the Crankshaft Position Sensor & Cam phase sensor. I stopped them at this point as I didn't have the money to replace the timing-belt, belts water-pump, & both of these sensors = $800-1100 just to see if that fixes my complaint.

Suggestions please !
 

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Greetings,

Without more detailed data, it's difficult to say: would suggest investing in a OBDII Data Scanner, so you can see the readings the ECM is reporting..

(For a low-cost ( Laptop/USB ) based scanner, see my sig.)

You mentioned running +20% rich: if the short term / long term fuel trim values are above (0), that would indicate running -lean-, a -20% value would indicate running very rich, FYI.

If the motor is in-fact running +20% lean, that would indicate a fuel delivery issue: would recommend checking the vacuum connection at the Fuel Pressure Regulator, and if that is good, would then recommend hooking up a fuel pressure gauge tester, to check fuel pressure at the fuel rail..

If you haven't already, also recommend signing up at the kiatechinfo website (see my sig.) using Internet Explorer, signup is free: then you can navigate to & view the [Service Info] for your vehicle,

Hope this helps,

Regards,
GottaCruise
 

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2002 Rio Cinco 1.5
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Discussion Starter · #3 · (Edited)
Hey GottaCruise...thanks for the input.

The mechanic that installed the upper o2 sensor was a diagnosis from code PO172.
They wrote on my receipt that prior to the new o2 sensor that the readings were +20% rich and after the new o2 sensor that the readings were back in speck and maybe even slighty lean. The "Engine Light" hasn't come on since installing the upper o2 sensor.

It just feels like the fuel-air mix is starved during initial acceleration.
P.S. I never stand on the gas or brakes.

While at the KIA Dealer, they also checked the fuel pressure at the fuel Rail and it was 50 P.S.I. (within speck of 46-51) which eliminates the fuel pump. Their recommendation to look at the sensors under the timing cover is based on their KIAtech database I assumed. They told me they called their headquarters Tech Line.

Unfortunately I don't have a PC computer. Only an Apple/Mac.

Any further ideas are greatly appreciated before I give them the green light the look under the timing cover. Can the Crankshaft Position Sensor be tested ? or is better to just replace it ?
 

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2002 Kia Rio, 2011 Kia Sorento 2005 f 250 1996 geo metro 1992 f 150
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Don't overlook a blocked cat i had similar issues At 134K but i had no power to get up a little hill and it did idle very bad and codes misfire cylinder 1/4 p0170 and P1166. and do clean the intake and IAC valve with carb cleaner if you are capable of doing that. Good luck with it. Buy a scanner if you can afford it if you do your own work. Great piece of equipment for trouble shooting. Use maf cleaner on the MAF sensor only. good luck with it.
 

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Hey GottaCruise...thanks for the input.

The mechanic that installed the upper o2 sensor was a diagnosis from code PO172.
They wrote on my receipt that prior to the new o2 sensor that the readings were +20% rich and after the new o2 sensor that the readings were back in speck and maybe even slighty lean. The "Engine Light" hasn't come on since installing the upper o2 sensor.

It just feels like the fuel-air mix is starved during initial acceleration.
P.S. I never stand on the gas or brakes.

While at the KIA Dealer, they also checked the fuel pressure at the fuel Rail and it was 50 P.S.I. (within speck of 46-51) which eliminates the fuel pump. Their recommendation to look at the sensors under the timing cover is based on their KIAtech database I assumed. They told me they called their headquarters Tech Line.

Unfortunately I don't have a PC computer. Only an Apple/Mac.

Any further ideas are greatly appreciated before I give them the green light the look under the timing cover. Can the Crankshaft Position Sensor be tested ? or is better to just replace it ?
Thanks for the additional info, that helps.

From what I read, you are working with a good technician, so I would continue that relationship for the repair,

Given the mileage interval since the last TB change, I would begin to provision $$$ for that service,

In general, acceleration issues are fuel, air, or spark related, as all (3) are needed to properly fire the motor..

Since (fuel) has been Q/A'd via pressure test, and ignition components (spark) have been inspected,

one item on the (air) side I would check is the EVAP canister Purge Valve is working properly, this to make sure no illegal air is affecting engine vacuum,

and on the (ignition) side, I would inspect the coil pack connectors to make sure they are in good condition, test to make sure good (+12v) voltage is getting to the connector ends, and check both coil packs primary/secondary coils to make sure the resistance values are in the recommended range..

re: Hard Starting when cold, +1 to RonJohn's recommendations of cleaning the IAC valve, and intake plenum & throttle body (if needed), and if the replacement MAF was exposed to unfiltered air from the vacuum line issue, would also be cleaning the MAF with (CRC-Brand) MAF cleaner,

also re: Hard Starting when cold, I would also check the connection at the Engine Coolant Temp. (ECT) sensor, and compare the (temperature) value being reported by the sensor to the ECM using a live data scanner - a defective ECT sensor or bad connection can throw off the values reported, commanding extra fuel (causing hard starting)

re: live data scanner alternatives - if you have a bluetooth capable smart (android-based) phone, you can also get data monitoring capabilities by purchasing a low-cost ELM327 bluetooth module (hooks into the ODBII port), and use the TORQUE android application to monitor your engine functions on your phone.. There are also some lower-cost (standalone) live data scanner units available on the market (e.g. Autex brand)

re: Crank Position sensor - there are cursory voltage / resistance tests you can do, but to really determine if the sensor is working properly requires advanced diagnostic equipment capable of displaying waveform (scope) data, given the $$$ of the equipment, it would be less expensive to just replace the sensor for a "shade-tree auto enthusiast" like myself.

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Above said, if it was my ride, I would have a good comfort level with the technician / dealer servicing the vehicle.. It sounds like they are doing the right things to help get your vehicle running good again.

Regards,
GottaCruise
 

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2002 Rio Cinco 1.5
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Discussion Starter · #6 ·
I re-read the Kia Dealer invoice/diagnosis and it says:
Use GDS for Fault finding. No Faults in any system.
Test drove car, felt missfire. Rechecked for faults, none in system.
Removed spark plugs, no problem found.
Suggest inspect timing belt and related sensors.
Installed Mass-Air-Flow. Test drove car, still missfires at high rpm.

The KIA tech while test driving the car also noticed that the auto-transmission was shifting a little slow.
( I remember I had it drained & refilled it a year ago, but that shop didn't have a replacement filter-strainer and told me it would need one next time) and they had overfilled it by 1/4" on the dip-stick. I hope that is not a problem.

I just remembered that the chocking cold-crank issue didn't start until after I had the rebuilt starter installed 3 weeks ago. Hmmm !

Today's cold-crank made one of the belts slightly squeal before turning over.
and sometimes the engine feels like it is slightly shuttering at stop signs, almost like the timing is off.
The missfire only seems to happen noticeably with the AC on, in drive at stop signs.

I'm torn between investing $ or trading it in now.

kj
 

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Given that an upper O2 sensor had failed / that a replacement cleared codes, and you are hearing belt squeal on start,

I agree w/ ronjohn that a blocked cat. converter is a possible cause of the issue - restricted exhaust flow can & will produce the symptoms you describe,

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* If the cat. converter is partially blocked, given the age of the TB belt, I'd -strongly recommend- getting the cat. converter checked out ASAP: excessive back-pressure can cause timing to jump, or worse, the TB belt to fail -

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To rule out any electrical issues, I would recommend doing a thorough cleaning of the battery terminals & cables, and the ground points where the neg. battery cable connects to the frame, and inspecting / cleaning the motor ground strap, and would inspect the connections at the starter (should be tight and secure),

Would also recommend removing the accessory belt(s) and check to make sure the pulley on each component (A/C compressor, alternator, power steering pump (if equipped) are turning freely / not binding,

(e.g.: make sure a failing/failed accessory component is not putting drag on the motor),

Again, the fact the motor is not throwing codes except at high rpm could have a few different causes (e.g. poor grounds, electrical issue, a failing coil pack, exhaust restriction), but if original to the vehicle, would get the cat. converter(s) inspected / Q/A'd / checked out first.

Regards,
GottaCruise
 

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2002 Rio Cinco 1.5
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Discussion Starter · #8 · (Edited)
Given that an upper O2 sensor had failed / that a replacement cleared codes, and you are hearing belt squeal on start,

I agree w/ ronjohn that a blocked cat. converter is a possible cause of the issue - restricted exhaust flow can & will produce the symptoms you describe,

--
* If the cat. converter is partially blocked, given the age of the TB belt, I'd -strongly recommend- getting the cat. converter checked out ASAP: excessive back-pressure can cause timing to jump, or worse, the TB belt to fail -

The shop that replaced the upper O2 sensor told me that they had to force out the old sensor and stripped some threads as a result ! They said it torqued in but was weak. No leaks at this time.
and if that new o2 sensor ever had to be removed, a new Cat Converter would probably be required( they took no responsibility for their actions).
It is the original cat-convertor with 154,000 mile on it.

Note: the car passed the strict California Smog Check 6 months ago easily! wouldn't this show that the cat-converter is good ??? (update: Kia dealer just told me it should through a code if it's partially restricted)

Kia dealer visibly cleaned the dirty battery connections when they installed the Mass-air-Flow sensor last week.
 

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Given that an upper O2 sensor had failed / that a replacement cleared codes, and you are hearing belt squeal on start,

I agree w/ ronjohn that a blocked cat. converter is a possible cause of the issue - restricted exhaust flow can & will produce the symptoms you describe,

--
* If the cat. converter is partially blocked, given the age of the TB belt, I'd -strongly recommend- getting the cat. converter checked out ASAP: excessive back-pressure can cause timing to jump, or worse, the TB belt to fail -

The shop that replaced the upper O2 sensor told me that they had to force out the old sensor and stripped some threads as a result ! They said it torqued in but was weak. No leaks at this time.
and if that new o2 sensor ever had to be removed, a new Cat Converter would probably be required( they took no responsibility for their actions).
It is the original cat-convertor with 154,000 mile on it.

Note: the car passed the strict California Smog Check 6 months ago easily! wouldn't this show that the cat-converter is good ??? (update: Kia dealer just told me it should through a code if it's partially restricted)

Kia dealer visibly cleaned the dirty battery connections when they installed the Mass-air-Flow sensor last week.
If you are confident w/ the dealer diagnosis, then you are back to them checking the cam phase adjuster and cam/crank sensors / TB service.

Following links are FYI / may provide additional info on why checking the cat. converter was recommended (suggest viewing all videos)

Causes of Cat. Converter failure:


How to check Cat. Converter: "old school / main cat"


How to check primary Cat. Converter: (at the B1S1 O2 sensor bung)
O2 Bung Adapter / Pressure tester kit:
Three-way Exhaust Back Pressure Kit Star Products


How to check for exhaust restriction, using Vacuum Gauge:

How to check Cat. Converter using ODBII Data Scan Tool / IR Thermometer

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re: passed smog 6 months ago - that was 6 months ago. You stated your issue started 1 month ago, after starter change..

If you want to do self-diagnosis, you will need to invest in some (low cost) tools, e.g.: ODBII Data Scanner, Vacuum Gauge, IR Thermometer, Pressure Tester kit.

Irregardless, again will state it seems the KIA Technician & service dept. are addressing your issue well - keeping in mind this is strictly a 2nd opinion / I have not seen your vehicle in any way/shape/or form to do any diagnosis with the above tools recommended.

I wish you well w/ the repair,

Regards,
GottaCruise
 

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Discussion Starter · #10 ·
[/QUOTE] keeping in mind this is strictly a 2nd opinion / I have not seen your vehicle in any way/shape/or form to do any diagnosis with the above tools recommended.

Regards,
GottaCruise[/QUOTE]

Yes I understand and thank-you for your on-line forum input.

I'm continuing this thread in hopes that it may help others on the forum.

Because I'm not able to perform the repairs myself anymore, I have to pay shop rates of $100-145 per hour for labor plus parts.

so many expensinve variables to through a dart at and gamble for such an old Kia now. I'm still undecided as to invest another $1000 in a timing-belt kit + water pump + crank position sensor + cam phase sensor, or do I cut my losses and just let the car die. I'll let ya know.

Best
kj
 

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kj,

I agree it is an expensive maintenance interval - and if you are unable to perform the diagnosis / repairs yourself, then you may be best served contacting the dealer and discussing what other options are available, e.g. trading in vehicle as-is / purchasing a reliable new or used vehicle w/ warranty,

Or researching for any High School / College trade or vocational schools in your area that may offer a lower-cost repair option,

Or researching for any neighbors in the trade / technicians local to your area that may offer "after hours" repair services at a lower rate,

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If it was my ride, I'd be doing the hard math also: is it worth spending 1000-1500 on a known-quantity, that I own to repair, or invest (???) more on another vehicle..

I wish you well w/ the decision: please keep us posted on what you decide.

Regards,
GottaCruise
 
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