Film-Tech Forum ARCHIVE: Kia Fuel Injection Problems

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Posted by Mark Gulbrandsen (Member # 72) on 06-22-2003, 10:47 PM:

Ok all you home mechanics......Here's one for you......
I just rebuilt the top end of my 95 KIA Sportage. It had overheated and burned two of the valves, plus blew the head gasket....actually it probably happened the other way around. The engine runs pretty good again, but the check engine light comes on after it has warmed up and is sitting idling. It also idles a bit on the rough side, plus fuel consumption is somewhat higher than it was.

This is a pretty typical Bosch type injection system with single O2 sensor. So I checked the ECU to see what malfunction code I would get and it comes up with a code 17, which means there is a problem in the feedback loop. That usually means the Oxygen Sensor, or some other sensor has failed, but they say the Oxygen sensor is the most common problem in all cars that have them. Anyway, I've checked most of the sensors and they seem fine. Throttle position sensor, Cam position sensor, Mass Air Flow, ECU temp. sensor....all seem to be working fine. Compression is right up there where it belongs in all four cylinders. The Oxygen sensor voltage output also seems to be ok and does not seem to behave sluggishly at all, which might indicate that its bad. O2 sensor output starts at .45 volts when cold, then at idle as the engine warms up it drops to .19 volts. At high speed revving I saw .79 volts. Keep in mind that the DVM ssampling rate seems to be the limiting factor in observing how quickly the output signal changes. But O2 sensor changes are supposed to be very rapid.

So, Anyone out there have any ideas.....could it be the O2 sensor anyway? Or could something else be causing this.

P.S.
Believe me, this KIA has been to the top of many peaks around here and to places full size trucks can't go. Of course it has been beaten to death!!! It finally gave up on a trip to Logan canyon a while back. I think when I get it running correctly I'll trade it in on an old 1960's pickup [Smile]

.

Thanks for any suggestions!!
Mark

Posted by Steve Kraus (Member # 476) on 06-22-2003, 11:54 PM:

Over hill over dale
KIA car will ever fail

Posted by Paul G. Thompson (Member # 655) on 06-23-2003, 12:08 AM:

check the fuel filter.

Posted by Paul G. Thompson (Member # 655) on 06-23-2003, 12:08 AM:

Check the fuel filter and fuel pressure.

Posted by Phil Hill (Member # 371) on 06-23-2003, 01:14 AM:

Junk it and get a REAL vehicle....

>>> Phil

Posted by Paul G. Thompson (Member # 655) on 06-23-2003, 01:22 AM:

How the hell did I wind up with a double post? [Confused]

Posted by William Hooper (Member # 71) on 06-23-2003, 01:25 AM:

Fuel injection? How's that work?

3 40DCOE's or a couple of SU's/Strombergs on a straight 6 for me!

Posted by Sam Hunter (Member # 1119) on 06-23-2003, 07:09 AM:

Paul, the symptoms indicate a vacuum leak. Probably on your intake.
Good luck.

Posted by Mark Gulbrandsen (Member # 72) on 06-23-2003, 08:14 AM:

"Junk it and get a REAL vehicle...."
_______________________________________________________

Actually it was between a Land Rover and a Kia when and when it came down to it the kia still fit into places where no other vehicle could. Both were used vehicles and I figured that if it rolled....or literally rolled off a mountina top or something like that it wasn't any great loss..... I also just couldn't bring myself to own a vehicle with tushy warmers in the seats [Roll Eyes]

.

Thanks for the suggestions so far. I think Paul has brought up a good point as I have not replaced the fuel filter, nor checked the fuel pressure. A new set of plugs I put in it have no deposits at all and they have been in there for a couple of hundred miles..... looks as though its running too lean to me. But that doesn't explain the poor gas milage.....
Mark

Posted by Bill Enos (Member # 440) on 06-23-2003, 08:50 AM:

Choice between Kia and Land Rover? You made the right choice. Although you would not get stranded in the boonies in the Land Rover, it probably wouldn't get to the city limits.

Posted by Jim Spohn (Member # 1547) on 06-23-2003, 10:16 AM:

Mark...I was trying to trouble-shoot An O2 sensor problem on my BMW. A tech told me to disconnect the sensor and the computer would go into a default setting (and of course the CHECK light will be on) but the real deal is to see if the rough running problem after warm up goes away. It seems that since O2 sensors have a heating element in them, when you start the engine the computer ignores the O2 senson until it has had time to warm up and then it starts reading it and this is why the rough running comes in after the engine has run a while. Hope this helps...Jim

Posted by Randy Stankey (Member # 64) on 06-23-2003, 03:54 PM:

Have you looked at the EGR valve? (Or whatever it's called.)
The tube that goes from the exhaust manifold to the intake. It's got a solenoid valve on it. When it opens, it's supposed to recycle exhaust gas back to the intake.

When the engine is cold, it's supposed to let warm air into the intake. When the engine is hot it will shut off. When the engine is somewhere in between, the computer will calculate the proper valve opening based on the readings from the O2 sensors, et. al.

If it's stuck open, you will get poor mileage and less performance when hot. If it's stuck shut you'll get poor mileage and poor performance when cold. If it's stuck part way or leaking, you'll get shitty performance all the time. My Neon had an electrically actuated solenoid which ran a vacuum operated valve. Thus, electrically the thing can appear to work but inside it's stuck.

For my car, the test was to hook a hand operated vacuum pump up to the solenoid and apply suction to it while the engine was running. Alternately applying and releasing suction should open and shut the valve and cause the engine to run differently. It will either pick up or lose a few RPM. If that's good, the next check was the electrical part. If that was good, the next check was the lines and connections to the engine computer.

My Neon gave me at bitch of a time about this for a while. I had it in the shop 3 times and I finally told them to replace the whole damn thing... The valve, actuator, wires and even the computer. Never had a problem with THAT again!

If Sam's suggestion it right, I imagine that could fall into line with what I am thinking... A faulty vacuum system can't properly actuate a vacuum operated part.

Posted by Sam Hunter (Member # 1119) on 06-23-2003, 08:08 PM:

In my previous post I mention Paul, I meant Mark.
Sorry.

Posted by Bruce McGee (Member # 131) on 06-23-2003, 10:16 PM:

I think there may be a vacuum problem also. Possible bad intake manifold gasket.

I just had this problem with my 1984 Ford truck with its 4.6 litre six. Replaced the intake/exaust manifold gasket. Rough idle and somewhat overheating conditions are gone. I even rebuilt the carburetor thinking that this was the problem before I replaced the gasket.

Posted by Sam Hunter (Member # 1119) on 06-23-2003, 10:42 PM:

A vacuum leak in the intake manifold will cause the engine to run lean and lean will make the engine overheat a little. One old trick mechanics used to use to detect leaks was to take a propane bottle with a rubber hose on the end of the valve and they would just barely turn it on and move it around the manifold. When it got near the leak the engine would speed up.
You may be able to find it with a mechanics stethoscope. Also, somebody mentioned the EGR valve, that will cause you problems as well. But I would look at it like this: If the care didn't have that problem till you performed work on it then something you did caused the problem.

P.S. Has anybody ever messed with an AUDI with the mechanical fuel injection system? I think it was a mid eighties series.
Those things were funky to the max, five cylinders and all. We had a Geo that had 3 cylinders as well. funky stuff.

Posted by William Hooper (Member # 71) on 06-24-2003, 01:31 AM:

quote:
Has anybody ever messed with an AUDI with the mechanical fuel injection system? I think it was a mid eighties series.

The 1967-68 Triumph TR-5 had mechanical fuel injection by Lucas. In the US, it was available only w/ SU carburettors, & called the TR-250. A few TR-5's were imported to the US by enthusiasts who became some of the first ECT patients in US mental hospitals.

Posted by Bruce McGee (Member # 131) on 06-24-2003, 07:44 AM:

My dad owned a 5 cylinder Audi 5000. Owned is the word. He rarely got to drive it. It lived in the dealer shop. He sold it, moved back to GM and Oldsmobile, and never looked back.

Posted by Per Hauberg (Member # 529) on 06-24-2003, 12:57 PM:

What about room for a DP70 in a KIA ?
That car doesn't fit a man of Your format, Mark !

p.

Posted by Mark Gulbrandsen (Member # 72) on 06-24-2003, 07:55 PM:

Actually Per, I have had a DP-70 head in the back of my KIA a couple of times. Thats probably what contirbuted to blowing up the engine. I guess you could call this KIA an expanded format KIA Sportage. When it comes to cars I've always been cheap! Except for the Dodge V-10 pickup I once had. 10 DP-70's in the back of that truck and you'd never know it [Cool]

. You would just stop and fill up at every cheap gas station on the planet!
Mark

Posted by Per Hauberg (Member # 529) on 06-25-2003, 07:57 AM:

With a DP in back of a Kia You just might risk the same complaint from road police as i did, when having loaded 2 70mm and 8 35 mm prints of My Fair Lady in back of the Volvo:
I was stopped and told that my headlights were dangerous to the air traffic !

p.

Posted by Mark Gulbrandsen (Member # 72) on 06-25-2003, 09:47 PM:

Today, I first double checked the timming belt to be sure I was not one tooth off and found it to be where it belonged. Then I proceeded to tear down the intake side and when I removed the PLENUM I found this.......I put the dam gasket on backwards (Yellow Arrows) [Embarrassed]

!!!

I'm pretty sure this must be the problem, and one could certainly equate this finding to the CODE 17 I was getting back from the ECU as a feedback loop error...it was also the only error it spit out at me...fortunately. With the gasket between the Plenum and the intake manifold on backwards the EGR passage between the EGR valve and the Plenum was not sealed. Not only would this affect the EGR operation, it would also cause a vacuum leak into the plenum. Couldn't see it though as the plenum comes up and over the injectors to the throttle body that you can see at the top. So it was hidden. This definately proves that haste makes waste! In this case had I not hurried through putting it back together and had paid more attention to what I was doing I wouldn't be wasting my time troubleshooting it. Will report back in a day or so as I now have to get some new gaskets from the dealer!
Mark

Posted by Sam Hunter (Member # 1119) on 06-26-2003, 10:45 PM:

The last time I rebuilt an engine I had a piston left over [Big Grin]

Gotta take your time on those things Mark, That should fix your problem when you get that vacuum back to normal.

Posted by Mark Gulbrandsen (Member # 72) on 06-27-2003, 06:41 AM:

Yea, thats pretty amazing Sam that you guessed the problem!! I'll pick up the parts today and put it together tonight. While its apart this far I'm also replacing the "O" rings on the injectors and cleaning them with the back flushing method.
Mark

Posted by Sam Hunter (Member # 1119) on 06-27-2003, 08:52 AM:

Should you mess with the injecters at this point?
Touchy little bastards you know.

Posted by Mark Gulbrandsen (Member # 72) on 06-28-2003, 04:24 PM:

The gasket was the problem. While I was waiting for the local KIA dealer to get a part he didn't have in stock I took the injectors in and had them professionally done. It was 19.50 per injector which wasn't much cionsidering that KIA gets $300.00 each for them. Never beieve a KIA dealer when they say maintainance is also cheap [Eek!]

.

At a pro fuel injection shop the injectors were first flow tested and the spray pattern analyzed. With my 4 injectors the flow rate was off almost 20% on one of the injectors while the other three were within 12% of each other. There was no leakage at all. The injectors get disassembled as far as plastic injectors do and then they are ultrasonically cleaned while cleaning solution is run thorough them and the coil is pulsed. They are then put back together and new filters and "O" rings are installed. They're then checked again for flow matching, leakage, and spray pattern. Before I tore down that side of the engine I did a visual of the spark plugs, and took some readings off the O2 sensor with a DMM. The look of the plugs and the readings I was getting hinted at a lean running engine. Anyway, a mismatch of even 10% is not satisfactory for fuel injectors! Mine now match with in .5% and what a difference it makes in the way the thing runs. It idles so smooth now you'd think it was a V-8. Now I can have it inspected and I'm pretty sure it'll pass.
Mark