Engine will not accelerate?

Good morning,

Can you check for codes?

It sounds like there may be a communication issue with the fuel pedal and the throttle body.

https://www.2carpros.com/articles/reduced-power-limp-mode

You can have it read for free at a parts store or you can buy a cheap reader for the codes.

Roy

Yes,the only code that came up is a p0301(number one cylinder misfire). When i changed throttle bodies i noticed a sludge type fluid in the intake. I cleaned it out. Could a bad PCV valve be causing that. Seems that it's choking itself out. In the old days,rebuilding a carburetor with new jets would solve problems but these newer vehicles have got be stumped. Only 81,000 miles on vehicle.

Okay, I would start by doing a compression test to be sure the cylinder is good.

https://www.2carpros.com/articles/how-to-test-engine-compression

Beyond, it could be an injector, coil or plug.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Also, since that cylinder is the furthest away from the fuel pump, check the actual fuel pressure.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Roy

Failed throttle bodies are common on these and will not set a code most of the time unless you hold the pedal down for thirty seconds when it acts up. Also the low side fuel pressure sensors go bad all the time and will cause a rough idle, stalls at times, lack of power.

Is the low pressure fuel sensor located on fuel line from tank before direct inject pump?

That is correct according to the picture provided.

Do you have a scan tool that can monitor the fuel pressure?

Roy

On same problem with fuel pressure. When i disconnect wires for low side fuel pressure sensor should you notice a change in idling?

No, you will not. All it does is send a signal to the ECM for the pressure. It has no effect on idle controls.

Roy

Should intake where throttle body attaches have a sludge like fluid in it? What would cause that to happen?

No, it should not.

You need to clean that out. I attached a guide for you to clean it.

https://www.2carpros.com/articles/throttle-actuator-service

What about the compression test for number 1 cylinder? Did you test that?

Roy

Unable to get my hands on a compression tester at this time. Can you tell me where and how that sludge like stuff came from so i can try and correct that prob also?

It comes from blow by from the engine and it collects at the throttle body. It is normal and the throttle body service is a normal service at 50,000 miles.

Roy

Would changing PVC valve help eliminate that? I understand some is normal but there was quite a bit in there.

No, it will not. As I stated, it is normal to have a build up over a period of time.

You still need to do the compression test.

Roy

Okay, thanks Roy. I'm working on getting a compression tester.

You are welcome.

Keep us updated.

Always glad to help.

Roy

Engine idles and runs great in park or neutral. Can rev engine to max in park or neutral with no fault codes. But when I go on the road car seems to not accelerate after 3rd gear. Good throttle in reverse. Have cleaned and/or replaced most sensors. Has new turbo and throttle body. Re-calibrated throttle body at cold and hot temperatures. Car runs great when parked. No fault codes. No smoke from exhaust. Could it be it just needs software updated? Been doing work on my own vehicles for 35+ years and have been able to figure out all vehicle problems but this has me stumped. Any suggestions would be greatly appreciated. Thank you

Fuel pressure is good. Also replaced DI fuel pump. Good cylinder pressure. As previous no fault codes.

Good morning,

the first thing I would do is to check the back pressure in the exhaust. the engine may not be able to breathe under load.

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms

You remove the upstream O2 sensor and install a back pressure gauge to read the back pressure.It should not have more than 1.5 pounds of pressure.

If you do not have a gauge, I would unbolt the front exhaust and drive it and see if it is any better.

Beyond that, this could be a transmission issue.

Roy

Wouldn't a problem with O2 sensor throw up some sort of fault code? Have had O2 sensors bad on other vehicles and a fault code always came up indicating such.

Yes, it would. When their readings are out of their set parameters, a fault code will be stored.

Roy