Jacob0015

Hello all,
So today I decided to change out my coil pack housing connectors because when I did a spark plug tune-up I noticed they were brittle and cracking so I bought some replacements. I took off the necessary parts, replaced the connectors, put everything back together, and went to start up the car. It started, idled rough for a few seconds, then just died. After that, I heard some weird on-going hum/buzzing sound coming from somewhere near the throttle body. I'll now go into the specifics of what I messed with to hopefully isolate the problem.

First, I took off the cover that covers the timing belt.

Then, I unscrewed the two Philips head screws that held the part of the air intake that connects from the throttle body to the air flow sensor.

I then took off the 5 bolts that held the throttle body into the side of the engine where the headers are. Note that on the bottom right bolt, the actual long metal piece that the bolt goes on (I forgot what it's called, the screw or something) broke so that one piece had the bolt on it and the rest appeared to be in the hole. I'm assuming this because the screw or long metal piece or whatever that had the bolt on it was rather short compared to how long it should be to stick in the hole and still have some of it stick out for the bolt to latch on to.

Sorry that was somewhat confusing, anyways I then took out the top two screws on the throttle body to separate it from the spacer. I also disconnected the throttle cable so I could move over the throttle body and I disconnected a hose underneath the throttle body. This gave me some access to the spark plug bay. I also disconnected an electrical connector to the back left of the throttle body (from an open hood froward view) and one from the front right (so that I could move the throttle body left).

I then took out the top two screws on the spacer in hopes of removing it so that I had more room but it was difficult to remove and I just gave up and let it be.

I then replaced all the plastic connectors for the 3 coil packs. I made sure I kept the proper orientation for the two wires per coil pack and clicked them into the new connector. I then attached the connectors to their proper locations.

After all that, I re-attached the bottom hose to the throttle body and attached the throttle body to the spacer (after putting in the 2 screws for the spacer) with the 2 top screws.

I then attached the 5 bolts on the side of the engine that holds it (along with the broken screw which tightened fine) and re-attached the 2 electrical connections I had off.

I re-attached my throttle cable with the right positioning of the 2 nuts to the throttle body.

I re-attached my air intake and secured them in (there was no openings on the 2 flexible plastic/rubber pieces on either side).

Lastly, I put back the timing belt plastic cover and went to start the engine.

I got the problem, went back, undid everything, checked that there was no debris in the coil pack connectors and that they were seated properly, and then re-installed everything. Problem still persists.

I had no more daylight so I had to call it a night and did some research. Got stuff on air flow sensors and throttle body settings and some valve that could have come off a cam gear, things that may be relevant to my problem.

Finally I decided to post here and see if anyone has any suggestions as to what I should do. I didn't really mess with much and it seems that a lot of people get this same problem from a lot of different tune-ups they do, which is rather strange. Hopefully there's some universal solution or something.

Thanks for reading through all this. Any suggestions would be greatly appreciated, I just want to get back to driving my Lexus, thanks all.

lexo98

iTrader: (2)

Have you tried to disconnect the battery? Try it a couple times.

Jacob0015

Alright will do thanks! Actually I was thinking of that, since I disconnected some things I thought that maybe the car just has to reset some stuff or something like that, everything's all monitored by the computer, glad to see that I wasn't the only one thinking of that haha! I'll give it a shot tomorrow.

ronsmoove

Same thing happened to me after i did my tune up. Came to find out that my coil pack wires were in bad shape and they were touching each other. I wrapped them both with electrical tape and made sure that they were not touching each other and problem was solved.

Jacob0015

Ah, that may be it too. I did notice that they were exposed and could be touching. I'll try this out after I test the battery thing. Going to do it now, I'll keep my laptop with me and keep you guys posted. Thanks for the replies!

Jacob0015

Question:
You know how there's two wires per connection for each of the 3 coil packs right? When you said you covered them with electrical tape, did you cover each wire per connector separate or did you cover the two wires together?

ronsmoove

I taped each wire seperately. 2 were exposed and they were touching and it took me awhile to figure out why the car kept cutting off everytime i started it and then i saw the wires touching. i taped them, seperated them, and that fixed the problem.

Jacob0015

Okay I'll do that later on today when the temperature goes down. In the meantime I disconnected my battery and reconnected it and the car started up and idles fine. I drove it for like 20 seconds and it didn't die (not a very intensive test though). The problem is, my VSC and VSC OFF lights came on and my check engine light is on. The check engine light still reads ignitor circuit. Did I really screw something up?

ronsmoove

how is your acceleration? you may need new coil packs. I did my own tune up and taped those wires but I still had bad acceleration. I took it to a mechanic and told them what was going on and I ended up geeting my coil packs replaced all together and the car is now running full power. Sometimes when you do a tune up on these cars that has over 100,000 miles, it may be time for coil packs to be changed also.

lexo98

iTrader: (2)

For the past 60000 miles whenever I disconnect the battery it's hit or miss if its gonna start right or give me problems. Disconnect the battery again and see if the lights go away.

Jacob0015

Okay sounds good I'll give these suggestions a shot. I'm hitting 200k miles so maybe it is time for new coil packs, but I'll test my acceleration first later today.

Jacob0015

Alright so I went and un-did everything again and made sure to tape up and exposed wires and I made sure they didn't contact each other and I put everything back together. I erased the code on the car and disconnected the battery. I reconnected it and started it up and went for a little 8 and a half mile test drive. Car seems to run fine and accelerates fine. I'm a little concerned about the idle speed though, it seems that when the car's in drive and at a stop, the revs are a little low. I noticed this issue yesterday when I disconnected and reconnected the battery and started the car. Yesterday the car ran and I parked it on the other side of my driveway and then this morning I went to start the car and it died on me. Not sure if this will happen again tomorrow or if I fixed the problem completely. Will keep you guys updated. In the meantime, does anyone know how many revs I should get when the car's in drive and at a stop?

sinstrex

iTrader: (2)

Its the maf sensor. Funny it doesnt evn throw a code. Happened with me. I changed it and it never did it to-date

Jacob0015

Okay thanks for the suggestion. Where is the MAF? And any ideas where I could get one for a good buy?

To keep updated, I started up the car this morning and it seems to run fine, the idle speed seemed to be normal. Maybe taping up those wires separate from each other did the trick. Hopefully it doesn't act up.