Fuel delivery issues

[kenpile]

A few weeks ago my 2013 Hyundai Genesis 5.0 R-Spec with 108k miles started playing up. For the last 8 months I have only been doing infrequent short trips in it due to now working from home. A few weeks ago I drove it 3 miles to the grocers and then the engine started to run bad as I pulled in to the parking lot. I spent abot 40 minutes buying groceries and then the car started ok but after about 2 miles home it stopped all together. After a while I was able to start it again and got it home misfiring badly.

The DTC code suggested low fuel rail pressure and missfire on cylinders 7 and 8. I replaced the fuel pump filter and all the ignition coil packs. I got it started OK but then after a while it started misfiring again. The DTC now shows P0300 or multiple miss fires. The battery and alternator are good and I have also replaced the fuel tank air filter.

I beleive that the engine runs OK from cold because it is bypasisng the oxygen sensors until it warms up, but then the problems start.

Has any one had a similar issue? I really don't want to go to the dealership!

 

[arcman]

First thing I'd be investigating is the fuel pump control module. Then low or high pressure fuel pumps. Get a mechanical gauge and connect to the low pressure line. You could run that into the cockpit or on the windshield and monitor while you drive. That controller is a common fail.

 

[kenpile]

Thanks for the tip. I'm not sure this car has a fuel pump control module. I can't drive it either because once it's warmed up it stops running.

Today I fugured out how to get data from the OBD II scanner and most things look good except the fuel rail pressure shows as 788 psi ( should be around 2200 psi I believe ) and the bank 1 O2 sensor 1 and bank 2 O2 sensor 2 throw a code ( P0130 and P0150 ) but the output voltage read correctly at ,455 volts each so I'm a bit confused there. One step forward though

 

[arcman]

The module is in the trunk. O2 sensors are throwing codes 'cause there's not enough fuel.

As I said... get a mechanical gauge on the low side fuel rail and watch it. If it's not steady from startup to when it shuts off, you've got a low press problem. If you don't want to do the gauge thing, replace the controller.

 

[kenpile]

The module is in the trunk. O2 sensors are throwing codes 'cause there's not enough fuel.

As I said... get a mechanical gauge on the low side fuel rail and watch it. If it's not steady from startup to when it shuts off, you've got a low press problem. If you don't want to do the gauge thing, replace the controller.

When you say the fuel pump control module do you mean the regulator? I've ordered one as I too think that is the main suspect now.

I eventually figured that the O2 sesnsor data showed just that they are giving a bad reading, not the sensors are faulty. Bad on me!

I'm not keen on buying a gauge for a one off job, especially as I beleive you also need a special Hyundai adapter also. This will be my last resort. Thanks again

 

[arcman]

I just noticed you're posting in the wrong group. Disregard anything I posted previously.