Engine Doesn't Rev Beyond 3000 Rpm

[MAS]

Hi All,

I have a Hyundai Tucson 2L petrol automatic. The car was not run for the past 1 week. Started running again since yesterday. It ran fine. Pumped fuel last night at Laughs. Today morning it started and ran well driving to work. Stopped at a joint to grab some breakfast. Afterwards it was difficult to crank it up again. Approached the office and the car stalled near the security check point. Again cranked it up with difficulty. Parked the car and put her on neutral. I could not rev beyond 3000 rpm. The car cooled down for about a hour and I went again to crank it up. It started well. It revved normally up to 6000 rpm (didn't go beyond that). There is no CEL light.

Some advice please.

Thanks in advance.

[Rumesh88]

Sounds like a case of fuel starvation due to a fault in the fuel pump or a clogged up fuel filter. But usually this situation should give out a fault code because the ECU would detect a lean running condition. But you may need to keep the peddle pressed for a certain period (may be 10 - 20 seconds) when the RPM caps off at 3000 for the ECU to detect it.

[MAS]

Sounds like a case of fuel starvation due to a fault in the fuel pump or a clogged up fuel filter. But usually this situation should give out a fault code because the ECU would detect a lean running condition. But you may need to keep the peddle pressed for a certain period (may be 10 - 20 seconds) when the RPM caps off at 3000 for the ECU to detect it.

Thanks. After the car cooled down after a hour it was all good (possibility of fuel pump and filter issues are less here ne). Maybe the symptoms will start once the engine is warmed up again. I am reading on the net, could be possible faulty crank shaft position sensor.

[Rumesh88]

Thanks. After the car cooled down after a hour it was all good (possibility of fuel pump and filter issues are less here ne). Maybe the symptoms will start once the engine is warmed up again. I am reading on the net, could be possible faulty crank shaft position sensor.

Not exactly. During cold start the air/fuel mixture is kept enriched by the ECU thus slightly compensating for drop (within limits) in fuel pressure. Also do not discount the possibility of an intermittent fault in fuel pressure regulation. Next time when the revs end up at 3000 RPM floor the throttle down for about 10 seconds and see if the CEL comes.

Edited December 8, 2014 by Rumesh88

[Crosswind]

Rumesh is bang on target in his diagnosis. In Hyundai and Kia vehicles, check engine light doesn't switch on for some petrol pump issues. Get the vehicle scanned. You will find the error.

[MAS]

Rumesh is bang on target in his diagnosis. In Hyundai and Kia vehicles, check engine light doesn't switch on for some petrol pump issues. Get the vehicle scanned. You will find the error.

I have a scanner.... no codes found. But I will floor the throttle down as Rumesh88 has advised. Maybe it will generate something.

[harshansenadhir]

whilst you're at the diagnosing of fuel feed related issues, also look for any coolant losses and signs of overheating.

How was the engine response when you were cracking after it stalled? was it a free cranking or stressed slow cranking ?

[MAS]

whilst you're at the diagnosing of fuel feed related issues, also look for any coolant losses and signs of overheating.

How was the engine response when you were cracking after it stalled? was it a free cranking or stressed slow cranking ?

It was a stressed slow cranking. However, there are no issues since yesterday. Fingers crossed. The car was not run for only one week !

[harshansenadhir]

It was a stressed slow cranking. However, there are no issues since yesterday. Fingers crossed. The car was not run for only one week !

if it was stressed slow cranking, there's a higher probability that engine was over stressed / heated. Check your water level both in radiator and expansion tank. Plus check the oil level as well. Did you notice any unusual reading of the heat gauge ? also check for operation of auxiliary fans as well.