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I did change the MAF sensor , replaced the PCV valve , and cleaned out the dielectric grease on all the coils connectors. I finally drove the car. The throttle was sluggish and but after 2500 rpm, it started to feel normal. Idle was rough. When I ran the codes, it was misfiring initially on 3,4, and 8 but the vast majority of the time, it was on 2,4,6,8. I just read another thread where a few others had a similar problem. In addition, I got a P0172, rich condition, for the first time.Dielectric shouldn't be a problem unless its too heavily coated interfering with metal connector to metal connector union.
I get that people are gonna do what they are gonna do, but I've never understood using a pressure washer under the hood. Degreaser and light rinsing from a garden hose has always done the trick for me and is very unlikely to send water into places it's not supposed to be.
I can agree and disagree. Pressure washing uses way less water but if used incorrectly is a problem. A garden hose at any distance if just coming from the end (unregulated or “pressurized) can flow 20 gpm. That amount of water can flood areas of easy penetration such as a coil boot, much easier. Honestly, it’s just about paying attention and aim. If you have neither, hire someone else. Still, I’m sure op is close once those boots and or coils get replaced. Next we can argue whether cold, hot, or warming engine is bestI get that people are gonna do what they are gonna do, but I've never understood using a pressure washer under the hood. Degreaser and light rinsing from a garden hose has always done the trick for me and is very unlikely to send water into places it's not supposed to be.
That's because you've probably never owned a modern BMW. Degreaser and 50 psi ain't going to cut it.I get that people are gonna do what they are gonna do, but I've never understood using a pressure washer under the hood. Degreaser and light rinsing from a garden hose has always done the trick for me and is very unlikely to send water into places it's not supposed to be.
Neither will a chainsaw or angle grinder cut through the grime, but that is one of the joys of owning "The Ultimate Driving Machine"That's because you've probably never owned a modern BMW. Degreaser and 50 psi ain't going to cut it.
Honestly, for me. I dont care how the engine looks. Why clean it at all. As long as its clean enough to track any oil leaks and such. Just IMHO.I get that people are gonna do what they are gonna do, but I've never understood using a pressure washer under the hood. Degreaser and light rinsing from a garden hose has always done the trick for me and is very unlikely to send water into places it's not supposed to be.
I cleaned my engine 6 days ago with simple green and then pressure washed. I noticed that my battery died in the process, so I charged it and it started and ran the engine for 5 min. The following day, I wanted to see if my battery would hold charge and it started but required high RPM (>1000) to maintain the engine from stalling and I could smell the gas from the exhaust. I ran for codes and it displayed P1126, which was magnetic clutch malfunction/short and I then began troubleshooting. I checked the resistance in the APS, TPS, magnetic clutch and motor resistance as per manual and everything was within spec. With the ignition on, I could see the throttle valve move with me pressing on the accelerator. For good measure, I cleaned the perimeter of the throttle body with a cleaner and rag and also cleaned the MAF sensor. Still it didn't idle correctly, so I took out all of the coils and found cylinder 1 and 3 to have some water around it. I used a air compressor and dried the coils as well as blew out the water polling in the engine. Only found water in cylinder 3, but then removed the spark plugs in 1, 3, and 2 and the plugs looked ok. I put back the coils, plugs and intake and hoped that it would all work but it still was rough idling. I ran for codes and now, it is P0300, P0301, P0303, P0308. Random misfiring. I am concerned that the water could have affected the many electrical connectors in the engine bay. I looked over the camshaft position and crankshaft sensor for retained water, but it seemed dry. I then cleaned every electrical connector with a cleaner and put dielectric grease in the connector.
I am so sorry for the long post but it was the only way that I could describe my thought process and troubleshooting. I just bought the running car last week and I wanted to clean the engine bay thoroughly, to look for gasket leaks and the power steering leak. I have no real experience troubleshooting cars and thought that the experts in the forum might be able to lead me down the right path.
what should I do next? replace the coils in 1,3, 8? I just purchase the techstream cable, will this help me troubleshoot and how do I use it?
thanks for any input.
I pressure washed my 06 lx470's engine and after a week there was misfire on cylinder 5. I swapped the coil with a known good ignition coil and the misfire went away. Upon inspecting few of ignition coils in my car, I found tiny cracks on it. I don't want to spend 400 dollars on replacing all the coils. I just replaced two for right now and will replace the rest one by one in future.
Unfortunately, I cannot figure it out. I thought that with a OBD2 reader and some tinkering and research, I could have solved my stupid mistake. Since my last update, I replaced all the spark plugs, (bank 2 plugs were fouled up) and changed the O2 sensors (upstream). I was convinced that the O2 sensor was faulty because I would see little voltage variation in bank 1 O2 sensors with increases in RPM. Most of the time, it was completely flat while bank 2 sensor acted appropriately. Right now, when I use my reader with live data, I feel like bank 1 sensors are not being read by the ECU, but I have no idea how to troubleshoot this. I feel like it most be a fuse that controls it or a connector along the way from bank 1 sensors to the ECU. I will think about it overnight and if nothing comes up, then I will bring it to a real mechanic to help me troubleshoot it.What's the latest on this story @rolo68 -have you solved this issue?
No, I am not sure how to do that.. I have thought about it but it seems so unlikely from a pressure washing. It also does not explain why bank 1 O2 sensors are not responsive and being read by the ECU.Have you ruled out valve timing issue on Bank 2?
Well that socks. Sorry to hear that. Have you replaced any of the coils?Unfortunately, I cannot figure it out. I thought that with a OBD2 reader and some tinkering and research, I could have solved my stupid mistake. Since my last update, I replaced all the spark plugs, (bank 2 plugs were fouled up) and changed the O2 sensors (upstream). I was convinced that the O2 sensor was faulty because I would see little voltage variation in bank 1 O2 sensors with increases in RPM. Most of the time, it was completely flat while bank 2 sensor acted appropriately. Right now, when I use my reader with live data, I feel like bank 1 sensors are not being read by the ECU, but I have no idea how to troubleshoot this. I feel like it most be a fuse that controls it or a connector along the way from bank 1 sensors to the ECU. I will think about it overnight and if nothing comes up, then I will bring it to a real mechanic to help me troubleshoot it.
I just bought 2 new coils and I will change it in the morning just in case. Seems odd that they would malfunction since it was dry when I removed them and bank 2 coils are blocked with the intake.Well that socks. Sorry to hear that. Have you replaced any of the coils?
You know I thought abt that way back when you u first posted. Maybe your issues are not related to the pressure washing. Regardless good luck and keep us posted.I just bought 2 new coils and I will change it in the morning just in case. Seems odd that they would malfunction since it was dry when I removed them and bank 2 coils are blocked with the intake.
You could probably trust this advice from a guy who's avatar looks like his... ^^^I have no idea how much water, or the amount of high pressure you used but it caused a misfire, which could have been enough force to cause belt to jump a few teeth especially on a wet, maybe loose timing belt. The point that 2,4,6,8 all threw codes would make me want to check timing on that bank to rule that out. Its well explained in the other thread you posted a question in, and also in the FSM for timing belt service.
Basically you would rotate the crankshaft where the mark on the crank pulley is pointing to the 0 degree timing mark. Remove PS cam cover to inspect punch mark on cam gear is lined up with the check mark on the behind the cam gear. It may take two full revolutions of the crank pulley to get the cam gear to line up-
We can walk you through this if you need help.