Chugging

[Monocle]

Hi All,

Been a while as I haven't had any problems!

My IS220D '07 has just passed 100k miles and is 1000 miles after its last Lexus service (Lexus FSH).

On Saturday I pulled out of the driveway and the car "bunny hopped" for about 2-3 seconds before driving normally. I had thought I had slipped off the clutch as my normal seat setting had been changed. Drove 40 miles and parked up for the weekend.

Yesterday morning the car cut out in first gear a couple of times on my drive to work. Then it got worse. No power below 2,000 rpm on numerous occasions and mostly in the lower gears. Ended up driving at high revs for long periods to see if it was a dpf issue. No difference.

I had not got any warning lights at this stage. I disconnected the solenoid from the EGR to see if that was the problem. Car drove smoothly but was limited to 1,600 rpm. I didn't get to test this for long as I was running late. Reconnected the EGR and the faults lights remained. Cleared these by disconnecting the negative terminal.

Got home eventually with the same issues and cleaned the EGR valve. This is something I try to do every 5k miles but it had been about 15k since the last clean. It was pretty badly coated (3-4 mm of carbon). The spring was working freely.

I put all back together and drove it this morning. The car is driving much better but there is still the odd chug. I also filled up with Redex to give a bit of additional cleaning.

I am hoping this is not the start of something major. I will be taking to Lexus as soon as I can but I'm hoping someone could shed some light on this.

I know there have been endless topics around similar issues but out of all the posts I have read, I can't find the symptoms that specifcally match these.

Also, since I didn't get any warning lights (apart from the usual when I disconnected the EGR solenoid) will Lexus diagnostics pick up anything? Are errors logged that don't give warning lights?

Thanks in advance.

[is200 Newbie]

To better describe the "chugging" is it more like the car shivers?

[Monocle]

Thanks Newbie.

I suppose chugging may not be the right word but it is not shivering really.

It feels like the car is running out of fuel.

On today's run (40 minutes, 40 miles) it ran well although there were a couple of instances when accelerating in low gears from low revs.

Overall, since I made the adjustments, the car is running far better but since the problem is not completely resolved I am anxious to know what is/was behind it.

[is200 Newbie]

I had what seemed like fuel starvation on mine a few months back and figured out it had carbon build up or possible build up - I put some fuel additive BG44 in the tank and ran with Shell petrol for a few fill ups, put another can of additive in after a few fill ups and it improved.

I have been told, whether it is true or not, from a friend who had an old IS300 that not having the fuel filler cap on tight enough would affect the fuel delivery as he done this on his and it wasn't running right until he noticed the cap was loose. I think having it on tight creates a vacuum but what that does to the fuel feed I don't know.

Easy to check though

[Monocle]

Thanks!

The fuel cap issue was mentioned in a previous post and I checked that. Seemed tight as always.

Everything is pointing towards build up as being an issue as performance has improved greatly with the Redex addition, >3,000rpm for 30 minutes at 75mph and EGR cleaning. Maybe I am being impatient as things are getting better.

I'll report back in another tank or so...