Miata Turbo Forum - Boost cars, acquire cats. - Starts will not REV over 4K or idle help

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Starts will not REV over 4K or idle help

Last year I turboed my 1992 Mazda Miata 1.6 with mspnp2 460cc injector afm deleted and installed the GM sensor it ran beautifully up to 12lbs until this year I drove it hard it forth to full boost let off the throttle on a decline heard a loud bang potential backfire continued my drive home parked the car for two days went to go for another drive made it about 5-10 miles north and it felt biggish was unsure so I pulled over everything checked out under the hood revs kinda seemed slipshod on the tach engine eventually would not move anymore i pulled over and the pedal led the throttle to keep it alive when I stopped the car died and has only ran normal once since the car reads 22.4 AFR and will only stay on with pedaling the throttle however the other day I unplugged the firing order and coil pack redid it the car started perfect revel to 7k and idled for 7mins or so straight and suddenly died it’s only done that once I’ve replaced plugs wires coil packs fuel filter fuel pump is reading proper psi timing is set perfect Compression within spec I’ve noticed today when I took the air filter off my turbo spins then stops and shortly after it stops the engine dies I’m out of ideas here anyone who can shine some light here I’d be great full!

That was a long sentence and very hard to follow. Did you have a question i could help with?

fix your popped coupler.

It is probably what brain says.

Is this a new problem? When you say it won't rev over 4K, is that free revving or under a load while driving?

Couplers are fine cant drive it cause it wont stay idling

post a log file of trying to keep it idling.

Take a log and post it? I'm wondering if the vacuum line to the map sensor is disconnected or kinked.

usually runs stupid rich if that's the case. BUT if there's an exhaust leak now near the o2 sensor, I could sorta of see this behavior.

we need to figure out what happened that's made the fuel so lean that it cant idle. if it was just a coupler, it would idle fine but not make boost. if it was a lost map sensor hose, youd be running off the 100KPA row and rich as shit at idle.

Thanks guys, i ran out of breath trying to read.

maybe had decel cut "off" and blew the guts out of something. maybe even destroyed the cat?

I’ll take a log weds morning, as for the wideband it new and it has no cats or mufflers

you need to upload the actual .msl file. then we can all look at the data

I do not see an icon for uploading files

go advanced reply- click the paperclip. attach file.

That is an idle screen shot? You tps is farked.

edit: and mat, and clt.... vref wire?
edit again: nope looked at wrong window... tps

THats me feathering the gas to keep the car alive or it dies

Well, then turn time based ae off. It will be very difficult to diagnose with 16msec pw swings at idle. I am assuming you still have the stock tps?

1.6 didn’t come with variable tps I’m running a bmw tps

Quote:

Originally Posted by Joensm0826 (Post 1471775)

1.6 didn’t come with variable tps I’m running a bmw tps

really? ~sigh~

Dude, have you done anything for yourself yet as far as looking at that log, or did you just come here looking for somebody to solve this for you? YOUR TPS IS SWINGING NEARLY 100% and you have massive spikes in injector pw. I don't even need to open the log files to see this.

you know what, screw it, I'm out.