Car still going into low boost mode! Options

[toyotacrazy]

My car is progressively going into low boost mode. I have the led "safe mode" monitors. At first it would go into LBM (low boost mode) after idle for a while on a hot day. Then, on the highway for about 20 minutes on a HOT day it would go to LBM. Now after about 10 minutes on a cold start, it goes into LBM. I started checking coolant temp. sensors with the ohm meter and checking over the harness for bad wires and connections. But I couldnt find in the toyota manuals what this one sensor does or how to check it. The only thing I can figure is its on of the many sensors that give the ecu the ok to boost. Anyways, I pulled on the wire (lightly) and it broke. So Im going to price one at toyota tomorrow. Can anyone confirm what sensor this is and what it does? Sorry for the long post. I thought you may need my reasoning for messing with the sensor. BTW its the sensor in the middle of the picture on the back of the block. Its suppost to have a single wire come out of the top and a connector. Thanks



This post has been edited by toyotacrazy: Aug 2, 2007 - 7:51 PM

[lagos]

im pretty sure thats a coolant temp sensor for the AC system. the engine does not use it.

can you describe to me, exactly what happens before and after you go into low boost mode? what were you just doing? how did the car feel? how much boost are you running, etc...etc...etc.. the more details the better.

btw, have you checked the ecu for codes?

This post has been edited by lagos: Aug 2, 2007 - 8:28 PM

[toyotacrazy]

im pretty sure thats a coolant temp sensor for the AC system. the engine does not use it.

can you describe to me, exactly what happens before and after you go into low boost mode? what were you just doing? how did the car feel? how much boost are you running, etc...etc...etc.. the more details the better.

btw, have you checked the ecu for codes?

Yea no codes. Today I drove on the highway after a cold start. I didnt boost past 5-6 psi. After about 10 minutes from the time I started the car, It went into safe mode. This happens mostly on the highway. This was with the a/c off. Before the a/c being on seemed to make it go into safe mode quicker. I dont use the a/c anymore. This condition used to happen on the same trip only closer to my house, after I sit at a light for a few minutes. Then if I would drive 40 mph for a few seconds, it would boost normally again, vsv would be normal also. Now it stays in low boost mode once it is set.
The car runs great. It feels fine. Im running 15-16 psi. only when the led's are on green. The few times I tried to boost when they were red, I couldnt boost past 12-13 psi.

[lagos]

After about 10 minutes from the time I started the car, It went into safe mode

besides the led's not changing color, what did you feel the car do?

[toyotacrazy]

After about 10 minutes from the time I started the car, It went into safe mode

besides the led's not changing color, what did you feel the car do?

It wont boost as high. It lacks some power. Not much.

[lagos]

and let me guess..... you normally notice this while cruising on the highway, not city driving, right?

have the screws on your afm ever been messed with? i suspect that you have a damaged afm. whatever you do, keep your boost as low as possible while you figure this issue out. god only knows how lean your car is under full boost because of the afm.

[toyotacrazy]

and let me guess..... you normally notice this while cruising on the highway, not city driving, right?

have the screws on your afm ever been messed with? i suspect that you have a damaged afm. whatever you do, keep your boost as low as possible while you figure this issue out. god only knows how lean your car is under full boost because of the afm.

Yes. It happens on the highway now. The one screw that is an adjustment has been tampered with. I bought a new afm from someone on this sight. He said it was from an mr2 turbo. It cant be. The inlet is 1/2 inch smaller in diameter. I guess that was a waste of money.

[lagos]

whats the part number on the afm. that should tell you where it came from.

DO NOT BOOST until you fix the problem. i had a similar issue with my afm. one night i was just cruising and the a/f ratio pegged lean. the engine had no power at all, and i had to pull over. a second later everything was back to normal. i took apart my afm, cleaned the contact strip and pickup arm inside, and soldered all the contact points back to the circuit board. the problem hasnt come back since, and my a/f ratio under boost got a lot more rich.

if you find out that your afm is from a wrong car, then replace it. if its from an st185 or mr2, then you might be able to repair it.

[toyotacrazy]

whats the part number on the afm. that should tell you where it came from.

DO NOT BOOST until you fix the problem. i had a similar issue with my afm. one night i was just cruising and the a/f ratio pegged lean. the engine had no power at all, and i had to pull over. a second later everything was back to normal. i took apart my afm, cleaned the contact strip and pickup arm inside, and soldered all the contact points back to the circuit board. the problem hasnt come back since, and my a/f ratio under boost got a lot more rich.

if you find out that your afm is from a wrong car, then replace it. if its from an st185 or mr2, then you might be able to repair it.

I turned the boost all the way off. Im running at wastegate minimim. Im going to take my afm apart and see what I can find. I also brought my fluke meter home to do some ohm checks. Ill let you know what I find

[toyotacrazy]

My afm part # is 22250-74170
can anyone verify this to be the correct one?

[lagos]

yeah thats the same part number as my afm. do the mulitmeter tests on it. then, open the big black cover on the afm, and take good pics of how it looks inside.

[toyotacrazy]

yeah thats the same part number as my afm. do the mulitmeter tests on it. then, open the big black cover on the afm, and take good pics of how it looks inside.

I finished all the ohm tests as in the toyota manual. It all tests good. Do I just take a razor blade to the glue and carefully pry it up?

[lagos]

yes.

what readings to you get from VS-E2 with the flapper door fully open and closed?

[toyotacrazy]

yes.

what readings to you get from VS-E2 with the flapper door fully open and closed?

fully closed is 362 ohms
fully open is 62 ohms

[toyotacrazy]

I dont know if these pics will help you or not. I dont see anything wrong. Are the little fingers on the inside of the afm, where the harness plugs in, suppost to be soldered?

This post has been edited by toyotacrazy: Aug 3, 2007 - 6:07 PM

[lagos]

dood... did you just remove your harness plug!!!!!?!?!?!?!?! that right there ****s the afm up! you should NEVER unscrew that harness plug!!!!!

also, is your pickup arm (thing that goes across the black strip) sitting in the middle of the strip like that on its own? its supposed to be resting all the way to the left, when the flap is closed.

This post has been edited by lagos: Aug 4, 2007 - 2:11 AM

[toyotacrazy]

dood... did you just remove your harness plug!!!!!?!?!?!?!?! that right there ****s the afm up! you should NEVER unscrew that harness plug!!!!!

also, is your pickup arm (thing that goes across the black strip) sitting in the middle of the strip like that on its own? its supposed to be resting all the way to the left, when the flap is closed.

Yea. Ive never had one apart before. I put it back together. It should be fine. Ill just solder the harness plug back together. The harness plug had been out before I got it. Maybe thats the source of my problems. Oh well.

[lagos]

The harness plug had been out before I got it. Maybe thats the source of my problems. Oh well.

yes. if that plug was ever out, then that is the reason for your issues! once that plug is removed, it brakes all the contact points from the circuit board. you might be able to just slide it in, and the car might start up and seem like its fine, but once you start driving, the vibration of the motor will make those points loose contact, and youll start getting all sorts of strange issues.

put the plug back in, and solder the contact points to the circuit board. if you do it correctly, you might be able to repair the afm. if your issues continue or get worse after the repair, then you need to start looking for another afm to buy.

[Gary]

What Art said, the harness plug should NEVER been removed.
It will damage the solders inside.
Always UNCLIP it, NOT UNSCREW it.
BTW, your Vs-E2 readings look normal.

[toyotacrazy]

What Art said, the harness plug should NEVER been removed.
It will damage the solders inside.
Always UNCLIP it, NOT UNSCREW it.
BTW, your Vs-E2 readings look normal.

There are 3 clips that I took off and 2 solder connectors that I believe were already unsoldered. I dont see anything wrong with this maf or anything to clean. I adjusted the pickup arm back to where it was. Im waiting for the fipg to set up to try it on the car

This post has been edited by toyotacrazy: Aug 4, 2007 - 3:06 PM

[toyotacrazy]

I just relocated my maf in front of my drivers wheel to get it away from the heat of the engine. Also this will allow cool air to be sucked into my engine bar instead of hot air as before. I drove it for about 20 minutes today and no safe mode! I will know for sure on the way to work tomorrow.

[lagos]

hot air is not your problem. the fact that your harness plug was removed before is whats causing your issues.

[toyotacrazy]

hot air is not your problem. the fact that your harness plug was removed before is whats causing your issues.

I think the maf was heat soaking. On cool days I didnt have any issues. When I had the maf out, I soldered the connectors back together. That also could have corrected my issue.

[lagos]

i keep trying to tell you, heatsoaking the maf wont cause safe mode.