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Top Swap having horrible idle, no power on throttle

grab that fat hose and pull it off, if it slide off with no effort its no good any more, its what 14 or 15 years old and dry and baked up.
 


That exhaust leak is absolutely your primary concern. Trying to figure out how to help you understand why.

Let's say you're driving down a road blindfolded that you're really familiar with, you kinda know where the curves and what not are by memory (open loop) so you're able to drive along ok, not perfect but good enough.

Now let's say instead of using your memory, you're going only by what your crazy ex-gf that hates your guts is telling you to do in the passenger seat (closed loop, 02 sensor not getting proper readings due to xover not bolted on).

The VE table in the pcm has a pretty good idea of how much fuel the engine needs to run at a given map value (which is what it does when you unplug your maf), so it just gives it that much fuel. As opposed to listening to the crazy ex (02 sensor adjusting fueling with bad data because huge exhaust leak).
 
99GT2dr said:
That exhaust leak is absolutely your primary concern. Trying to figure out how to help you understand why.

Let's say you're driving down a road blindfolded that you're really familiar with, you kinda know where the curves and what not are by memory (open loop) so you're able to drive along ok, not perfect but good enough.

Now let's say instead of using your memory, you're going only by what your crazy ex-gf that hates your guts is telling you to do in the passenger seat (closed loop, 02 sensor not getting proper readings due to xover not bolted on).

The VE table in the pcm has a pretty good idea of how much fuel the engine needs to run at a given map value (which is what it does when you unplug your maf), so it just gives it that much fuel. As opposed to listening to the crazy ex (02 sensor adjusting fueling with bad data because huge exhaust leak).
Click to expand...

Hahah great! I'm getting it fixed today. I'll update you when I have the crossover bolted on
 
99GT2dr said:
That exhaust leak is absolutely your primary concern. Trying to figure out how to help you understand why.

Let's say you're driving down a road blindfolded that you're really familiar with, you kinda know where the curves and what not are by memory (open loop) so you're able to drive along ok, not perfect but good enough.

Now let's say instead of using your memory, you're going only by what your crazy ex-gf that hates your guts is telling you to do in the passenger seat (closed loop, 02 sensor not getting proper readings due to xover not bolted on).

The VE table in the pcm has a pretty good idea of how much fuel the engine needs to run at a given map value (which is what it does when you unplug your maf), so it just gives it that much fuel. As opposed to listening to the crazy ex (02 sensor adjusting fueling with bad data because huge exhaust leak).
Click to expand...

I don't know you; but this analogy wins.
 


1. FWIW, I just double checked the file. The MAF tables are 99+, so that rules out that issue.
2. Stud extractors will work better on those rear bolts than anything, drilling will take you an exorbitant amount of time.
3. Once you get that fixed, you'll need to address the vacuum leak that's somewhere on that engine. This is where a scanner comes in handy, you can look at the fuel trims and know right off if you have a leak. You did plug the booster line back in after the swap didn't you? I've been guilty of forgetting that a time or two.
4. Your power steering pump is going out.
 
my top swap sounds exactly like yours in the video. I'll be watching this thread closely!

just fired up my top swap last night so i havent had a chance to troubleshoot yet.

update: swapped in my gt's mass air sensor and IAC, replaced some sketchy vacuum lines and for now...the idle is smooth and no longer sounds like the engine in your you tube video. now to fix the exhaust leaks.....
 
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Reptile said:
1. FWIW, I just double checked the file. The MAF tables are 99+, so that rules out that issue.
2. Stud extractors will work better on those rear bolts than anything, drilling will take you an exorbitant amount of time.
3. Once you get that fixed, you'll need to address the vacuum leak that's somewhere on that engine. This is where a scanner comes in handy, you can look at the fuel trims and know right off if you have a leak. You did plug the booster line back in after the swap didn't you? I've been guilty of forgetting that a time or two.
4. Your power steering pump is going out.
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You mean the brake booster right? If so, then yeah that's plugged in. And yeah I know my poor power steering. :(
 
Well guys, here is an update.
I fixed the exhaust leak and the vacuum leak to the best of my knowledge. that cleared up all engine codes except for the o2 sensor code. She was running much better but still had a rough idle, but drivable. Then two days ago, I started her up to take my girl and son to get some Panda express, not even 3 minutes on the road and i hear a LOUD cracking noise. Turns out I somehow sent 2 rods straight through the block. I wasn't even driving her hard. So, Now shes in the shop getting a new block and I'm $3100 poorer.
 
ugg im sorry bro thats hard news 3100 is a lot of money. I would cry. in case your not the type to cry ill cry for you
 


$3100 wtf!? You could get an L67 from a yard for $500, why so much? On CL I don't see many wbodies selling for even $2500, let alone more than that for just a motor.

After you finished the top swap, did you change the oil right after, run it for 15 or so minutes, then change it again? I use cheap oil for the 15 minute change, just to clean it out. Sorry to hear about this, hopefully it'll run good after the new engine for you.
 
99GT2dr said:
$3100 wtf!? You could get an L67 from a yard for $500, why so much? On CL I don't see many wbodies selling for even $2500, let alone more than that for just a motor.

After you finished the top swap, did you change the oil right after, run it for 15 or so minutes, then change it again? I use cheap oil for the 15 minute change, just to clean it out. Sorry to hear about this, hopefully it'll run good after the new engine for you.
Click to expand...

It's a relatively new motor with only 60k miles. 1 year warranty. It's the motor plus the install, and their going to top swap in for me. I called around all the shops in town and that was by far the cheapest. I just want it running lol. I would buy another car or what have you but didn't have $2500 sitting in my bank account or good enough credit to get a loan since I'm young and in college. Since I know the guys at the shop super well they're allowing me to make payments.

Yeah I did the post swap oil change.

Unforetunately it looks like my tranny is going to go next. Reptile has the shift points set at 5800 rpm. And from 2nd-3rd she was shifting at 6200rpm (probably why two rods blew straight through the block). Maybe a tranny fluid flush will fix it? or maybe it was the old motor? no idea.
 
You'd have to tear it down to find out what killed it. 6200 rpm certainly won't do it, though. Possible your oil got contaminated with fuel from running rich with the exhaust not bolted down, too late to check for that now.

For the trans I'd just do a pan drop and filter change, flush is asking for trouble. Maybe I should start swapping 3800's for people as a side job, had no idea that was the going rate. Not bad for ~6-8 hours of work.
 
Since you are low on funds why not just sell and get a GTP and keep it stock-ish? For that $3,100 you could have probably found a GTP right off the bat and been done. Time to search around for a good used GT trans and swap it in, and yea, don't flush the existing trans unless you want to kill it faster. And by new block do you mean a used longblock?
 


If he doesnt have the money, he shouldn't topswap the new engine what if it blows up again? which is a high chance it will.
and why are you flooring the car when the car isnt running properly and have no way to scan the car? no wonder it blewup.
 
Grimsin said:
If he doesnt have the money, he shouldn't topswap the new engine what if it blows up again? which is a high chance it will.
and why are you flooring the car when the car isnt running properly and have no way to scan the car? no wonder it blewup.
Click to expand...

If you read the entire thread, you'd see that I wasn't flooring the car when it blew up. I was taking a regular drive to panda express. I floored in maybe once or twice when we were very first trying to diagnose whatever problem the engine was having.
 
99GT2dr said:
You'd have to tear it down to find out what killed it. 6200 rpm certainly won't do it, though. Possible your oil got contaminated with fuel from running rich with the exhaust not bolted down, too late to check for that now.

For the trans I'd just do a pan drop and filter change, flush is asking for trouble. Maybe I should start swapping 3800's for people as a side job, had no idea that was the going rate. Not bad for ~6-8 hours of work.
Click to expand...

I'll do that then. Just curious, why would a flush be bad? The tranny is approaching 150k miles.
 
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