When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hello everyone. I recently purchased 2008 Lexus ISF with 170000km. Before making a decision this forum helped me a lot to make a right one
Yesterday I was driving and check engine light + traction control off + red exclamation mark + check VSC went on. I stopped and start checking the car. When turning the car on It felt jiggly, shaky. Like the whole car was vibrating. Also, the rev idle is jiggly, drops to 500 rpm and feels like the car will turn off but it does not (see file attached)
I went to the dealership, they suggested doing engine, sparkplug checking, filters cleaning. They said OBD showed a problem with gas being too "fatty" or fuel injectors are injecting too much fuel into the engine. I asked for the exact fault code but by the time he couldn't remember.
I checked the filter (see image) it is K&N sports filter.
Before replacing injectors etc, start simple. Replace the engine air filter with oem vs an oiled filled one like a K&N. And spray the mass air flow sensor with the CRC maf sensor cleaner and reset the codes to see if it comes up again.
^^^ what he said. K&N's slowly vaporize the oil that they use to filter the incoming air and over time it accumulates on and messes up the MAF. This could be causing your problem.
The good news its both banks so the problem is likely a central component, like an MAF.
Anyone else know what P1170 typically relates towards? I have seen this pop up on my end a few times - sometimes with a reset it is fine.
Vacuum / Air Leak?
The filter is drying over night. What should I do with oil build up in the pipe. Should I clean it? If so how? What material to use? This is how the pipe looks like (see images)
Rich sounds like an intake leak post-MAF sensor. It is metering X amount of air, but only Y is getting into the engine. Over fueling.
Port injector code is only there because the car is assuming something is wrong with the injectors because it's overfueling
Hi, thank you for reply.
So the shaking of the car and rev arrow is due to this too? This makes sense. Can you confirm you have seen the video attached?
So start cheap and work your way expensive. As mentioned above since it's a common thing to both sides, it points to a common issue. I'd suspect the maf, especially with a k and n filter. I'd replace the filter with a oem air filter, then try to cleaning the intake tubing and the maf. If this doesn't work I'd start considering the more expensive items, MAF etc.
That's a good amount of build up in the intake, I'd be worried what the MAF sensor look like. Give it a shot cleaning it with electronic cleaner and see if you can find the method for testing it.
In a naturally aspirated engine you'll never be under positive pressure, always negative to zero, this sucks air in, if this air is being sucked in after the maf it's unmetered air and would result in a lean condition.
In boosted applications you can be under positive pressure and negative pressure, if you have a leak after the maf then air would be sucked in during idle and off boost resulting in a lean condition, but under boost metered air would be pushed out of the tubing resulting in a rich condition.
Might be worth messaging this member in this thread as well as it sounds similar.
Rich sounds like an intake leak post-MAF sensor. It is metering X amount of air, but only Y is getting into the engine. Over fueling.
Port injector code is only there because the car is assuming something is wrong with the injectors because it's overfueling
Originally Posted by McPierson
Maybe I’m missing something, but an intake leak causes a lean condition.
The engine has a wideband O2, so neither of these things apply unless you're more than 20% off with fueling which would likely be an audible leak.
If it were mine, I'd clean the MAF first and run some injector cleaner like BG44K. You can clean the intake tube with anything you like, it won't be a big deal since that tube follows the MAF and the MAF is a primary source for tune information.
The engine has a wideband O2, so neither of these things apply unless you're more than 20% off with fueling which would likely be an audible leak.
If it were mine, I'd clean the MAF first and run some injector cleaner like BG44K. You can clean the intake tube with anything you like, it won't be a big deal since that tube follows the MAF and the MAF is a primary source for tune information.
Lance, do you think the K&N filter could be the culprit or is that all wives tale stuff?
04-27-20, 10:02 PM
Purchased ISF two weeks ago and this happened
