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Is My Motor Blown?

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Old 09-14-08, 10:35 PM
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Is My Motor Blown?

Bought my FD on thursday, drove it 20 miles home, then 20 miles to work friday. And it ran great. It also ran great when I test drove it previously. But on my way home on friday, i got off the freeway and stopped at the light. When it started idling, the car started chugging and rocking real hard. When the light turned green, I gave it gas and it almost quit. It moved forward, but weak as hell. I gave it gas real gingerly, and when I finally got it to go (around 10+ mph) it ran smooth again. But at the next light, started idling unstably and weak. When I got home, I checked the levels and the radiator was bone dry. I filled it up, and started it up, but all's the same. Saturday morning I popped the hood and found a vacuum hose broken off, so I replaced that. I also swapped out the XS reprogrammed computer for the factory one. No change. Still idles crappy as ever. Also noticed the boost gauge shows no pressure buildup, only vacuum. And the motor seems to run ever so slightly better when I have the hoses for the blowoff valve and the boost gauge disconnected from the motor. Is my motor blown? How would I know? Is there anything else I could check. I'm taking it down to Mazda's & More in Kent, WA tomorrow, but any input would be great.
Old 09-14-08, 11:54 PM
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Sounds like a vacuum leak to me, perhaps you blew a line off or a coupler. The way to tell if your motor is blown is a compression check.
Old 09-15-08, 01:01 AM
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One of the guys on a forum of mine had a somewhat similar problem, he had "blew up" the cat and all the chunks of what ever they are made of was restricting the exhaust flow and was keeping him at 5 pounds of boost from his normal 15 or so. He removed the chunks and everything was back again except he started to boost 16-17 pounds and he popped the head gasket on a run at the track. Hope that gave you a possible solution.
Old 09-17-08, 11:01 AM
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Well, got a compression test done by a rotary guy... Apex seal on rotor # 2 is blown. Compression on #1 is 95, 95, 95. Rotor #2 is 90, 0, 0. So there. Stinks. Gonna have to shell out $5000 for a rebuild (seals and a new housing). Don't have time or space to do it myself, and kinda need it asap. Anybody wanna donate a 20b? : )
Old 09-19-08, 10:59 PM
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Can't help you with that but I can help you by taking it off your hands if you ever plan on selling it.
Old 09-19-08, 11:44 PM
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there's a 20b for sale for 4500??
i just saw it in west sections, or u can easily get 1 from japan2la =)

he's the man
Old 09-20-08, 06:48 PM
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sell the FD ill buy it!
Old 09-23-08, 05:07 PM
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Hmm. Sell, huh? Well, I already have it being rebuilt, so I don't think I'll sell. I was thinking, however, about getting it street ported while it's in the shop. Anybody think that's a bad idea for a commuter? Well, I I should have said a freakin awesome bat outta hell commuter. But seriously, think it'll just blow up again?
Old 09-23-08, 11:01 PM
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RHD ftw!

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check the MAP sensor... that line can come off pretty easy and that'll make it run like ****...
Old 09-24-08, 04:58 AM
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Street porting has nothing to do with the engine blowing up again. It will greatly affect whether you pass emissions checks and how often you shell out at the gas pump.

Tuning and boost control have just about everything to do with whether it blows up again. And now that the engine is in pieces, make sure to have the injectors ultrasonically cleaned and tested before putting them back in.

Dave
Old 09-27-08, 04:43 PM
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Ok, just got back from the shop. Looks like plenty more is needing repair on the engine. All the vac lines need replacing (but I already knew that), the big wiring harness is all brittle from ambient engine heat over time and needs replacement, the turbos are cracked where they bolt on, and the engine still needs a rebuild. All said and done, it's gonna cost $7000+ and I can't afford it. Gonna list it to sell. Too bad to, cuz the body is perfect, the interior is awesome, got great wheels. Would've been one bad car. Oh well.
Old 09-27-08, 05:19 PM
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hope you didnt spend to much on that ride of yours...
Old 09-27-08, 05:53 PM
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hey

Something similar happend to me while I was racing on the track at sebring fl. Last track session of the day I lost all power, thoght I blew out the turbos( but no smoke). Car would not boost! Check everything from compression to leaky BOV's or anything i could check. it ended up being a hose in the lower intercooler hose about 3 inches long. I couldnt beleave i missed it, with all the times taking the car apart. hope this helps
Old 09-29-08, 12:23 AM
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you could do a quick ebay search and find about 3 complete 13B-REW swaps for $1800. I know there's no guarantees with these but it may be worth the risk. Also you can sell your blown engine for a good chunk of change (I know I'm looking for one) and also sell off the extra transmission (the $1800 swap comes with one). Now you're probably looking at $800-$1000 total.
Old 09-29-08, 08:56 AM
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Dont sell the car. You can have the engine rebuilt, and find some stock twins used alon with a better condition harness. An engine rebuild should only be around 3k, I live in Ohio and all of the shops are compeeting in price for around 3-3.5k for stock rebuild. you could get your car fresh and on the road with some nice upgrades for 5k.
Old 09-29-08, 10:13 AM
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Ouch! Not even a week and the motor goes? I've done that before >_<
Old 09-29-08, 04:30 PM
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Uhm. Not a very smooth introduction to the world of the FD. Unfortunately this scene plays out from time to time. What kind of gas were you running?

Good luck. As the others have said, $7k sounds like a fair but high number. If you do any work yourself, you could get a very nice motor and the other parts put in for half that price. I see complete motors in the classfieds pretty regularly.

Make sure when you get it running again that the boost is completely under control and set at a level appropriate for the fuel system. If you're not sure, set it at 10psi.

Dave

Last edited by dgeesaman; 09-29-08 at 04:32 PM.
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