karmen vortex possible issue...HELP!!

[86targatop]

Hi I just bought the car about 2 weeks ago and it will turn over but she will not stay running unless I am holding the accelerator. WILL NOT IDLE!! And at full throttle will not very or exceed 2100rpms...any suggestions? Thanx in advance

[cre]

Have you checked for diagnostic codes? How to do so is covered in the MKIII FAQ section. As for Karman Vortex, that's the type of airflow meter used in the 7M-GTE (turbo models) whether you've got a GTE or a GE (which is all that was available until '87)... well, I'm not sure why you bring that up unless you've already diagnosed more than you've posted. A bad airflow meter (either type) could cause these symptoms, so could a bad knock sensor or several other things. Check the codes and post back with whatever you find.

[supraheelfan]

sorry to highjack this thread but this could help us both..
I have a code 31,43,& 52. I know the code 43 is no big issue cause I've almost fixed that but the 31 and 52 are a pain. What other makes/models can i get a afm from that will work with my 87 7mgte? B/C it's getting harder and harder to find an OEM AFM or even a decent used one.
The code 52 will not go away, however the car drives normal with the code one, meaning no lose of power etc...

[supraheelfan]

Which is better to do: go ahead and replace the OEM AFM. -OR- going to MAF T? Or is MAF T Pro the only way to go?

[cre]

Have you rewired the knock sensor with GOOD shielded wire? There's a writeup on it which is commonly linked to here or you can find it via Google. A code 52 doesn't mean the car will be in permanent limp mode, just that the ECU is detecting a significant failure in the knock detection system. If the code keeps coming back, don't ignore it.

Depending on your goals you may want to just look for a good, used Lexus AFM and use the electronics from that in your KVAFM's housing. The electronics are the same it's the housings that are different. This will have you up and running a lot quicker and for less cash. I like the MAFT Pro, but if you're not out to upgrade to S/D or can't find a Lex AFM either the MAF T or MAFT Gen II will be a simpler install and setup.

[supraheelfan]

Thanks CRE
BTW, I did rewire the knock sensor by an import specialist 3 times and he swears the wiring is not the problem. The code 52 doesn't do what it normally would do, for instance the car has power through the entire powerband unless the code 31 comes up then it stalls go and stall again. I had the code 52 on the 7mgte for about 6 months and this doens't seem like a reg. code 52 causing all these problems. I've never had a code 31 and every since the code 31 it's been acting strange and I've yet to see this problem with a code 52. Plus the mech that fixed the knock sensor wiring did it very well with heat shield and extra care b/c I took it too him 3 times to fix the same problem (the code 52.)

[supraheelfan]

If I get the Lexus AFM do I need to upgrade xthe injectors to 550cc also? N/M i guess only need the 550cc injectors if you install the entire afm housing and not just replace the electronics on it.
Plus I want a more reliable sensor and more than anything else I want something that could help me tune the car eventually.

So to clarify a Lexus v8 AFM/Mass air flow sensor will work with replacement of sensor itself correct? For very helpful info: what other Toyota/Lexsus intake sensors will also work as air flow sensor without having to spend way too much on a used new afm
Plus CRE, the best bet would be to just purchase another 7mgte yellow plug ECU and hope that gets rid of the code 52.

[supraheelfan]

Bump!
Do you think switching out the ECU will solve the infamous code 52?
Code 52 has been showing up for at least a year but the car drove great?

Any suggestions to get the code 52 fixed: new( or used knock sensor from supracarparts.com) but they swear the sensor is good. 3 knock sensor rewires by an import specialists shop and still no progress. . All power is there no hesitation so (unless it's so obsolete that I can't even tell a difference when accelerating).