Air Flow Meter (1 Viewer)

[dglenn]

Trouble with Air Flow Meter? After a full rebuild on the top end of my 94 LC, I am now experiencing what is believed to be a air Flow Meter failure. At initial cold start, the car will not idle unless I feather the gas until it warms up then it idles well. I had a local shop put his diagnostic gear on the engine and he says I have a hard code Air Flow Meter failure.

I get with the guys at cruisers.net and they send me a used Air Flow Meter? I pop it on and get a similar experience with idle and at lite throttle up in higher gears at cruise. But Essentially, I can throttle through the rough spots and get er to run. Did cruisers send me a bad Air Flow Meter?

I drive over to a local friends house who owns a 94 LC. Swap his Air flow Meter assembly for mine, car appears to run fine at idle and under load on a quick trip around the block. Only thing that worries me is the car was warm at the point of trying his Air Flow Meter. I put the cruisers net part back in and I get a rough idle.

Should I be looking somewhere else for the source of poor to no idle? Also recently had the 15 AMP EFI fuse blow and shut me down. Can they be related? Thx for any input.

 

[gotmud]

Might want to also check your intake hose. Check the bottom side of the folds for any cracks. Hose should be somewhat pliable.

 

[Ozdunc]

Could also be your o2 sensor.

With the engine off
Bridge the E1 and TE connections with a paper clip in the diagnostics port inside the engine bay

Turn the key to the acc position - don't start the truck. The check engine light should flash.
If it flashes regularly all is good. If it flashes in a sequence then pauses then flashes again you have an issue with something. The codes flashed are two digit.
So an error 32 for example would be -
flash flash flash pause flash flash pause repeated
if you have 2 error types say 32 and 41 you'd get
flash flash flash pause flash flash pause flash flash flash flash pause flash pause repeated
so have a pen and paper handy.

If you haven't already got one get a Haynes or Ellery manual for your truck, they'll have all the error codes, plus all the test you can do to confirm parts work or not.

The O2 sensor would often show up as fine on the diagnostics but putting a analogue voltmeter on it shows that its only reading every so often or irregularly, but not enough to trigger the ECU.

Try a different intake hose first as thats the cheapest and most likely option, then check the o2 sensor, before jumping to the AFM as they are big biccies and you don't want to change that only to find its one of the other options

Hope this helps

 

[dglenn]

thx for the input, big help, will toy with that a bit and see what I come up with. I do have the haynes manual. My intake hose had some cracks in it at both sides and I have used some flexible tape to reseal. Does anyone know if the Mass Air Flow Meter can be cleaned?

 

[spdwaver]

thx for the input, big help, will toy with that a bit and see what I come up with. I do have the haynes manual. My intake hose had some cracks in it at both sides and I have used some flexible tape to reseal. Does anyone know if the Mass Air Flow Meter can be cleaned?

Get yourself a factory service manual from Toyota's information site (TIS), you will not regret it.

You can download a FSM of your choice for $15.00, giving you two full days (and, in some cases longer) to download whatever you need.

https://techinfo.toyota.com/techInfoPortal/

 

[dglenn]

thx for the input. yeah, I like the sound of the FSM. I contacted cruisers.net and got a second MAF sensor that appears to have solved the problem. thx again for all input.