Hyundai Forums banner

1 - 20 of 20 Posts

·
Registered
Joined
·
32 Posts
Discussion Starter #1
My 05 Santa Fe, 2.7L feels sluggish. It doesnt really get going until I get in the 3K RPM.

Has 145k miles, new NGK irridium plugs and NGK wires at 110k miles. Dealer changed timing belt around 105k mile, two trans flushes (1 @ 75k and one at 130k) new air filter recently. New Denso upstream O2 sensors in the last 10k miles, and one new Crank Position Sensor @ 135k miles.

Idles great, no check engine light, reader shows long-term fuel trim is near 0 (fluctuates between -3 -+3) depending on RPM. Unknown fuel filter status. I've never changed it.

Idles smooth, no noticable misses, transmission doesnt feel like its slipping.

But unless I'm running 3000 RPM, it's a gutless wonder.

Thought maybe plugged cat, but runs better at higher RPM.

Any thoughts?
 

·
Registered
Joined
·
32 Posts
Discussion Starter #2
A little more info:

At 3500 ish, RPM, it's like a power band, I get a noticable jump in power before it upshifts.

I need to give it 3/4 throttle from a stop light just to keep up with traffic and not frustrate the people behind my(for going too slow)

Of course with less throttle, the transmission will shift at a lower rpm, like it should, but I'm moving much slower than traffic under those circumstances.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #4
Thanks, I'll check it.
I replaced the timing belt on an 03. I see lots of tutorials on how to replace the timing belt, but am unsure how to check cam timing.

Are there timing mark's on the crank pulley, or would I need to look at the cam sprockets?

Thanks
 

·
Registered
Joined
·
2,850 Posts
You might try taking out the upstream o2 sensors and take it for a drive. It will be noisy on the drive, but if the power returns, you have a restriction in one or more of your catalytic converters.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #6
Thanks, I'll try that.
I did remove the front O2 sensor, put in a fitting and a hose with a gauge and ran it to 3000 rpm. Not very accurate, I know, the only gauge I had on hand was a 0-30psi but the needle didnt budge. I suspect a back pressure of just a few pounds would have a negative impact tho.
I'll try the O2 removal and see If I get any more power.
 

·
Registered
Joined
·
86 Posts
Please let us know what you find out. Mine has acted the same way for the 3 years that I've owned it. New OEM MAF, Crankshaft sensor, no vacuum leaks, and spark plugs and wires and it still feels slow until 3k RPM. I think it's just the nature of the beast. New cars nowadays have more horsepower than our cars and they also have more efficient gearing in the transmission.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #8
I purchased a back pressure gauge and put it in the O2 sensor hole and revved engine. Less than 2psi (a quick jump to 2, then settled back to 1)
Put my boroscope camera down the O2 sensor hole and looks good. I can see the cat honeycomb, no obstructions on either manifold cat. Drilled a 3/8" hole just ahead of the downstream cat, put my boroscope in that hole, and it looks good, honeycomb appears clean, and uniform like the manifold cats.

I'll try and look at the cam timing inspection later this week.
I also want to check fuel pressure. Replacing the fuel filter looks to be a bit of a pain and since the fuel pump has to be removed, might be prudent to put in a new one, but I'll check the pressure first.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #9
Additionally, since my oxygen sensors were out, I went for a drive without them installed. No noticable difference in performance, marginal at best.
Thought maybe the sound had me thinking a marginal increase in power, so I turned the heater fan on high, cranked up the radio and it felt like normal, gutless wonder.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #11 (Edited)
Pulled the upper timing cover off. Timing belt feels loose. Hopefully you can see the angle of the belt I was able to slightly pull with my finger.

Looks like I'm gonna be getting in there this week. Hopefully it's a simple tensioner.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #12
Ordered Aisin timing kit with water pump. Should be here tomorrow. I'll update when I can get to it on Wednesday.
 

·
Registered
Joined
·
243 Posts
If the belt was loose enough, could it have jumped a cog or two on the sprocket and now your timing is off? That could result in poor engine performance right? Did you see if the timing marks were lining up just to verify that has not happened?
 

·
Registered
Joined
·
32 Posts
Discussion Starter #14
Not yet, just pulled to top cover last night.
I'll pull the wheel, inner fender, and rotate the engine to align the timing Mark's to see where I'm at.

The belt was almost loose enough for me to make it jump a tooth, So I suspect, I hope, that is my issue. May not have needed it, but I got the entire pump/timing belt kit.

Will dig in within the next few days as work schedule permits
 

·
Registered
Joined
·
32 Posts
Discussion Starter #15
So I gained access to the timing belt. The timing was good. Since I was almost at the change interval. I changed the water pump, belt, tensioner and idlers. Tensioner idler bearings were noisy, and the water pump sounded like it had marbles as bearings (though not leaking through the weep hole)
I'll finish putting it back together this evening. I suspect since I did not find anything major, my problem likely still exists.
Next step is to test fuel pressure, then compression.
 

·
Registered
Joined
·
86 Posts
Replacing the fuel filter isn't too bad, but it does take some work! If you ever replace it, I suggest cutting the tab that holds the fuel temp sensor so that you don't damage it when removing it.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #17
Good to know, thanks.

I was surprised Hyundai recommends 55k change interval and they didnt use an external filter.

I'll check fuel pressure before I order a filter. Not sure if I should change the entire sending unit or not.

I like,,, not having a car payment. But not a fan of vehicle repairs:eek:
 

·
Registered
Joined
·
32 Posts
Discussion Starter #18
Got the pump, timing belt and associated idlers and tensioner installed. Topped off the coolant and test drove.

Weirdest thing, I have my power back! I can keep up with traffic without depressing the gas pedal far enough to make the transmission shift at 4000RPM.

Is shifts about 3000 rpm (less throttle) and using the steptronic, keeping it in second gear, I can maintain 25 MPH up this steep hill in my neighborhood, where previously I would loose speed to about 17 MPH.
Hate that I didnt find a "smoking gun", but happy it feels normal again. Maybe it was slightly out of time,?,,,,, dunno.

I will drive with my OBD scanner connected to record data and see if there are other changes in the coming days.

Thanks for the responses.
--C
 

·
Registered
Joined
·
473 Posts
You said the old belt seemed stretched?
That could retard the cam timing a bit while running even though it looked okay standing still.
I'm not familiar with this engine. Does it have a distributor that runs off the cam?
If so ignition timing would also be retarded by the tired belt
 

·
Registered
Joined
·
32 Posts
Discussion Starter #20
Yup, the old belt came off easy, while the new belt was a very snug fit with the tensioner loose.
I think it is a distributorless engine. (Not 100% sure tho)

I'm a technician by trade,,,just not an automotive tech,,, so I can wrench, but know just enough to get into trouble with cars.
I work for my county's fleet services and was talking to one of the auto mechanics about this. He said one theory was the loose belt, caused the timing to potentially be be off enough that the computer advanced, or retarded the timing electronically to compensate. Though he his experience with Hyundais is somewhat limited as the fleet we have consists of the mostly American company vehicles.

Anyway, I'm gonna check plugs. Just in case the previous issue fouled the plugs. More of a quick sanity check really.

I was getting about 13-14 MPG around town in this 05 AWD Santa Fe. I'll monitor it moving forward.
My last 2003 Santa Fe 2.7l AWD got around 16-17 MPG in town. So this vehicle wasnt being driven that much. My suburban gets better gas mileage and is more comfortable to drive.
Hope this helps fuel economy.
 
1 - 20 of 20 Posts
Top