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-   -   blown engine.. (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/blown-engine-282628/)

jamesuncw 03-14-04 12:05 PM

blown engine..
 
Looking for any positive info here.

was driving last night in 3rd boosting 12 on the secondary, then all of a sudden car fell on its face, no power, no boost, crazy vacuum fluctuation. Limp it to a gas station, car is shaking really bad below 1000. Revving it up to 1500 the vacuum smooths out at 14 and the engine doesnt shake.

mods are dp/mp/cb/intake pettit ecu, profec b

this sucks because i only have about 2500 on this engine.

oil looks fine, didnt see any coolant in it, coolant level is fine.

definately lost a seal?

i know compression test is in order, but first i have to tow the car about 50 miles back to my house.

Jayseven 03-14-04 12:11 PM

get a compression test. you will know for sure then. where in NC are you.

Fatman0203 03-14-04 12:12 PM

Possible Map sensor?

cruiser 03-14-04 12:44 PM

I second MAP sensor. Were you still able to get it up over 60mph ? Does it idle on its own (but rough) ?

jamesuncw 03-14-04 01:08 PM

oh yea , forgot, I also checked the sensor, well I tugged on it and it felt still attached, couldnt see in the dark. Possibly split?

also I have an upgraded radiator.

I dunno I was limping home about 40 didnt try and push it harder.

It will idle on it own, but shakes real bad at low rpm.

cruiser 03-14-04 01:47 PM

If it idles on its own its not your engine. You just got a bad vacuum leak somewhere. Does it boost ? Does it product A LOT of smoke under acceleration, especially at about 2.5k RPM when turbos should come online ?

Mine did the same when MAP sensor got disconnected.

jamesuncw 03-14-04 02:06 PM

Does not boost.

150kFd 03-14-04 10:42 PM

do you have a "check engine" light on? Could be the OMP went out and sent you to limp mode

jamesuncw 03-15-04 12:44 AM

Hmmm, I really hope thats the problem. CEL was on.

Jayseven, I'm in Wilmington

Snook 03-15-04 07:43 AM

totally trashed or blown motors still produce boost if you hold the throttle down long enough. You are in limp mode...you got very lucky! pull the code

jamesuncw 03-19-04 04:35 PM

code 11, intake air thermosensor.. would this cause it to go in limp mode?

RX7Wishing 03-19-04 05:21 PM

yep.

And it sounds like a vaccum line popped off somewhere. especially if your unable to boost.

allrotor93 03-19-04 05:26 PM


Originally posted by jamesuncw
code 11, intake air thermosensor.. would this cause it to go in limp mode?
get a pfc and dont worry about it. those pettit ecus suck ass.

SPR415 03-19-04 05:37 PM


Originally posted by cruiser
If it idles on its own its not your engine.
that's not always the case...some will idle on its own but very lumpy. also, you can still boost on a blown engine.

Fatman0203 03-19-04 08:05 PM

Disconnected the battery pump the break for 30 seconds and reconnect.

Beast From The East 03-19-04 08:11 PM

Replace the thermosensor
 
Don't know how many miles you have on it, but this is a very common failure part. What happens is the voltage on it goes wonky, making your car think it is very, very cold outside. A pfc won't eliminate this (as someone suggested), instead it will help you see the problem clearly. The sensor screen will show you the voltage that is incorrect, and your ait temps will show like -40C when it's summertime in California. That kicks in the air correction temp factors and that starts adding lots and lots of fuel. Since it's still warm out, you're end up running like 9 to one afrs or worse, so your car stumbles and you can't ever hope to get into high enough revs to build boost.

The sensor is in a suck place under the plennum - it's relatively cheap to replace. If you have an aftermarket i/c you should consider relocating it so it's not in the nasty heat sink.

Beast

jamesuncw 03-29-04 10:10 PM

well i did a compression test with a cheapo piston gauge. rear rotor got 75 on all 3 faces, i dont know if the guage was just that off.. ive heard of them showing 80 on perfect motors.. but.... the front rotor showed 17/5 /5 . I only had ~3000 miles on this motor running with the pettit ecu.. im pretty sure it wasnt running lean, al the plugs were black. Oh well, hopefully I get some assistance from the 1 year 12k mile warranty.. im not sure though. I'm really disappointed by this. i dont know whether to cut my loss or keep going.

911GT2 03-29-04 10:14 PM

I'm sorry, 17/5/5 on the front rotor? Ouch. That sounds like one blown seal and one badly chipped or cracked one.

That hurts man, especially after all the positive reinforcement you'd gotten. I hope the warranty covers it, good luck :(

RX7Wishing 03-29-04 10:16 PM

Damn that sucks!! looks like your front rotor is done.. If you got any mods you better take it them off beofre you take it in.. they will void that warrenty quick as shit

RX7Wishing 03-29-04 10:17 PM

P.S Was it a malloy rebuild?

jamesuncw 03-30-04 12:03 AM

No I mean I had it rebuilt by a rotor speciality shop, and the mods were on it when it was done... im so mixed feeling about this.. Hopefully the guy will help me out.. or at least compromise somewhat.. I mean I spent almost 5 gs on the motor alone :(

cpnneeda 03-31-04 03:15 AM

blown engine
 
5g's. Sounds like you need to enlist the help of a privateer. I know someone who would be a bit more compromising on the engine build, provided the shop you went to doesn't fix it resonably. Best of all, he's located in Wilmington. He knows his shit, and is building a 3rd gen w/ large street porting as we speak. If you get slammed again by the other shop, drop me an email, cpnneeda@hotmail.com, and I will contact him about seeing what he can do for you. This goes for anyone else in the area who isn't a do-it-yourselfer. I'm sure he wouldn't mind the business. Let me know something.

jamesuncw 03-31-04 10:22 AM

Are you talking about scott from gsm?

Well the builder told me to bring it up to Raleigh and that he will go from there. This is going to be fun trying to figure out how to get it up there.

tiger18 03-31-04 10:25 AM

only thing i can never figure out about these cars is why the hell the engine has blown up,,,hes just had it rebuilt,, (ohhh and even in limp mode car idles fine,,,,will just not boost,,,,,only light throttle)
when he says it was shaking on low tick over,,,,thats like he's running on one rotor,,,which explains the low compression in one rotor

cruiser 03-31-04 10:34 AM

Engine blows when there is not enough fuel delivered. You find the cause.


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