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86 toyota supra cutting out

i have a 86 toyota supra with a 3.0.i had just put a new feul pump, mass air flow,tps, and intake gaskets plus plugs and wires. so with that all said when i get the motor over 1800rpm its cuts out and drops 2 normal idle and then bounces back. it is alway yhe same spot. and if you try to hold idle ubove that it does the same. please help

Sounds like you could have a bad air mass sensor(even if it is new one) or forgot to connect the coupler to it. I’d be curious to know if the symptom you described occurs without the check engine light coming. By the way, Is that a 7M-GTE?

I had an '87 Supra Turbo 7M-GTE. Yours is prob. a 7M-GE because you didn’t mention turbocharged. I would guess the air mass sensor is causing the problem of all the things you replaced. BTW,the head gaskets were prone to blowing because the material was changed from asbestos to metal at the last minute but not the torque specs.

the head gaskets were prone to blowing because the material was changed from asbestos to metal at the last minute but not the torque specs
That is true, though other Japanese car manufacturers also used asbestos for the headgaskets until late 90’.
As for the 7M-GTE, the main problem would probably be the stiffness of the cylinder head. As I recall, for the Gr.A race, the head had to be put through the special heat treatment processs otherwise they would get distorted in the first 15 minutes on the dyno.

Have you considered a clogged catalytic converter?

“Other Japanese manufacturers used asbestos also”. So what?? That has zero effect on the Supra, it was a totally different engine, totally different design. The reason for the blown headgaskets was the low torque specs for the bolts holding the gasket down, since it wasn’t asbestos, but METAL!
It amazes me how people just want to argue over their senseless sh-t.

“Other Japanese manufacturers used asbestos also”. So what?? That has zero effect on the Supra, it was a totally different engine, totally different design. The reason for the blown headgaskets was the low torque specs for the bolts holding the gasket down, since it wasn’t asbestos, but METAL!
I believe Toyota uses asbestos for the 7M-GTE as OEM. Does that mean you replaced the gasket with the aftermarket part(metal gasket) but the engine still prone to blowing?

yes its a 7m-ge and the cat is gone for now but the mass air sounds like a good spot to start the conection is hooked up thanks for the imput. i redid the head gaskets so its not a issuue

If you replaced the the throttle position sensor it needs to be adjusted properly using a feeler gauge and an ohm meter. You can also verify that the throttle position sensor is functioning properly. Get a Haynes or Toyota service manual it will explain the procedure. It sounds like you’re hitting fuel cut which is tested by shorting the wires E2 and IDL on the harness side and increasing the throttle. Specification is to bounce between 1200 and 1800 RPMs. Also make sure that the throttle position sensor is plugged in. Check the mass airflow sensor plug and the bundle of negative ground wires underneath the intake manifold that the bolt is tight. I got some weird intermittent engine problems when it was lose once.