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Discussion Starter · #1 ·
hi,

all advice/opinions are appreciated.

850 Turbo wagon.

I've notice some hesitation while in traffic at 10-15 mph & around 60 mph.
I've replaced the MAF about 2 months ago and it solve a enginge cut-off problem.
Now it is throwing a code for the anti-knock sensor. My mechanic said to first try premium gas. I have done, and she still hesitates, but not total cutting off the engine because i give it gas immediately.

1. Could it be the anti-knock sensor. If so, how difficult would it be to replace.
Unplug/plug and done. Or major time effort?

2. If not the anti-knock sensor, where should i be looking next.

Thanks in advance!
 

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It could be the knock sensors.There is 2 of them on the front of the block.

It migth be easy to replace.I forget the exact years but there was an updated set that was kind of a pain to get them in for the first time.
 

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Discussion Starter · #3 ·
tech,

she stalled on me this weekend. i could get it to start back up, but the idle was terribly poor. as if 1 or 2 spark plug wires were pulled from the plugs themself. i managed to get her back into the garage by stepping on the gas fully, but then she would only go at a crawling pace.

i am debating about putting her into the gargage and let a professional replace the anti-knock sensors or doing them myself and saving on labor cost.

do you have step-by-step advice if i were to try it myself? what is the most difficult area? when i talked to the mechanic a few weeks back, he said they were the updated set that needs to be replaced.
with them being in front of the block, are there alot of parts that need to be removed to access them, if so, would i be getting myself into trouble ripping things out to replace the sensors?
 

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The worse part is removing the intake.

But if it is running that bad there might be soemthing else wrong with it.

Try pulling codes again.
 

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Discussion Starter · #5 ·
update.

took her in to replace the anti-knock sensors. after the mechanic pulled the intake, he saw that the (turbo exhaust wastegate hose?) was shot. so he replaced the ~3 foot hose without replacing the sensors and the previous stall problem has been cured thus far.



thanks for the info everyone.
 

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Discussion Starter · #8 ·
sorry fellas, i spoke (typed) too soon. On friday, she went dead again. the mechanic has it for the weekend. I'll report back when i get an update.
 

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Argh!

Well, keep us posted.
Thanks!
 

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Discussion Starter · #10 ·
-update-

had the '94 turbo wagon in shop. Mechanic ran diagnostic for several days. He finally determined that the cam position sensor was bad. He replaced it, it seems to run normal for now. I definately hope that it takes care of it this time.
Thanks for all the input thus far from everyone.
 
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