Car doesn't want to idle after new timing belt

njintau_fsd

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2003 Mazdaspeed Protege
So, my timing belt snapped on me on the highway last Thursday (on my birthday of all days, can you believe it!?) After a new timing belt and water pump, the car fired up but started idling kind off strange, plus my boost gauge was reading around 14-17 mm hg. At first, I got a P0106 but I think it was caused by a vac leak from a broken hose leading to a solenoid mounted behind the passenger side strut tower (I'm guessing its the purge control solenoid) and another leak between the IM and (I'm guessing again) the EGR modulator solenoid. I went ahead and replaced those vac hoses and even installed new coil packs just in case (the old ones were kind of squishy anyway.)

So far, that code hasn't come back but the car still runs like crap at idle and after warm-up doesn't idle at all. The funny thing is, when I drove it around the block or when I just revved the car, it ran nice and smooth, even the boost gauge started reading around 20-21 mm hg. Its just at idle, it runs like piss and is at 14-17 mm hg. Also, when I slow down, my wide band is at around 20.5, indicating its running really lean and when its idling, its either around 10.5 or 20.5.

Any ideas on what's causing this? I'm assuming this isn't due to bent valves since (assuming it idled at all) it would run like crap no matter what the engine speed was. Could it be IAC, EGR stuck open maybe? If the cams were off by one tooth with respect to the crank, would that cause this issue? The spark plugs looked like they may need replacing too, could that be the issue?

Thanks in advance! :D
 
Nobody? Come on guys help me out! :(

Btw, before anyone asks, I have a new O2 sensor in there and it has been working fine so far. Also, I don't think its low compression either because every time the engine died when warm, I was able to start it up pretty quickly plus it actually has some power when I accelerate.
 
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Hmm, I rotated the crank after I installed the timing belt four times (checked cam position after every two turns of the crank) and the cams seemed to line up each time. Do you think this will happen if both cams were off by a tooth? And wouldn't it run like crap at higher rpms too if the timing was off?
 
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First thing I'd do would be pop the timing cover off and just triple check that you're not off by a tooth. That's about the only thing that would be directly related to a timing belt replacement.

Next thing would probably be to look for a vacuum leak. If it's big enough to cause the car to idle funny, you may be able to hear a hissing sound when listening around under the hood.

If neither of the above pan out, you can try driving it around for a bit to see if it throws another code.
 
Update: Looks like you guys were right. When I rechecked the timing, the crank was off by 1 tooth. I guess when I aligned the cams, the crank pulley ended up moving when I put the belt on. After redoing the whole thing on Friday, she purrs like a kitten now! I guess fixing the vac leaks helped big time because now not only is it a lot smoother and doesn't bog down in neutral, the A/F ratios are almost spot on.

Also (and I'm venting now) the timing belt in this car was a major PITA! Idk if its the LSD in the trans but even though the car was on ramps, not stands, plus the trans was in 5th gear, the crank pulley still moved way too easily. I spent a good three hours taking off and putting on the belt over and over because every time either the exhaust cam or the crank went out of alignment. I finally managed to get it right after I fixed the crank gear by fitting a 21 mm socket and breaker bar, clamping the breaker bar to one of the ramps, then getting my stepdad to physically hold the cams in place via wrenches as I slipped the belt on. Jebus, I did not have this much trouble when I did the timing belt in my PGT!

Either way, thanks for the help!
 
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