Finally got around to driving my car on boost. Did some nice easy pulls in 1st-3rd. Then some near WOT pulls. Everything is good.. Did this for probably 4 miles. Runs good, sounds good, feels good, all sensors normal.
Btw this is 8.5:1, 370cc, s-afc2, t3/t4, stock maf (blow though), turbo xs bov, saab 900 intercooler. Set to 7 psi but after pressure loss I'm at 5 until I turn up the mbc but for now it's just at 5.
Anyway, started to drive back home. Just giving it a little boost here and there, still not trusting it fully. Got on it in 2nd and at something like 4-5000 it just kind of cut power or something. I still had my foot on the gas for a second and it was making boost still but going no where. Didn't sound bad like detonating. Sounded more like decelerating. Of course I was spooked and terrified. Let off immediately and drove it home nicely. I kept watching the rear view mirror for some huge blue cloud of smoke, but I got home fine. Besides this it runs great. I let it idle for 10 minutes while I scoured the engine bay for something loose or disconnected. Didn't find anything.
Not really sure what happened, but it definately has me spooked. Does this seem like the ecu pulled timing? That might explain the lack of power despite all the boost. It ran fine all the way home however. I'd think the ecu would pull timing and keep it off. But I don't know which is why I ask. I'm going to check my base timing again tomorrow and probably pull a few degrees (I'd like 17).
It might also be important to note that I've been fighting my ignition recently too. I have new plugs and wires in the mail, but for now I have old regapped plugs and plug wires I have taken off like 20 times. I've been fighting #1 to fire correctly since this morning. The wires are definately going out. But is that even reason for this type of thing to happen?
Like I said, tomorrow morning I'm checking timing, compression, and plugs.
Just not sure about this one.. any feedback?
Too much timing? Not enough Ignition?. **Kinda Long**
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PMan_S13
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Anyone? Even if you just have an opinion I am very open to feedback. You can't learn anything if you aren't willing to listen.
One more thing I noticed this morning. One of my intake pipes that hooks onto the downstream end of the maf is shifted about 1/2" farther than where I put it. Possible that, on boost, it seperated enough for boost to spray out and then go way rich? It's still connected, btw. Just pushed farther out than where I put it.
One more thing I noticed this morning. One of my intake pipes that hooks onto the downstream end of the maf is shifted about 1/2" farther than where I put it. Possible that, on boost, it seperated enough for boost to spray out and then go way rich? It's still connected, btw. Just pushed farther out than where I put it.
You might want to check your IC pipings. Whenever I did my shakedown run, my coldpipe popped off. And it ran rich and all that.
But I also have similar problem whenever I punched my KA-T @ second gear when the engine is still cold. The ecu pulled back the timing at around 2500-3000rpm.. and then It readjust itself and it acts fine again in third gear.
For your problem, Im thinking that It might be your ignition since you said you've been having problems with it.
But I also have similar problem whenever I punched my KA-T @ second gear when the engine is still cold. The ecu pulled back the timing at around 2500-3000rpm.. and then It readjust itself and it acts fine again in third gear.
For your problem, Im thinking that It might be your ignition since you said you've been having problems with it.
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C-Kwik
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Check your spark plug gap. With more air and fuel, there is more resistance in the gap. You need to shorten it from the rather large .044" factory gapping. I'm at .027" myself. This is a common issue for first time boosters. It will basically feel a lot like a rev limiter. And only occurs at or near WOT.
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PMan_S13
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I did move mine down to around .035" the last time I had the plugs out. I'm planning on running 9-10psi (or just shy of where ever my injectors can't keep up.) Should I close the gap even more? I was worried about it not having enough spark to run smoothly.
This morning I adjusted one of my IC pipes. It looked like it had been forced pretty far from where I installed it. It was the pipe right after the maf. It's possible that on boost air was leaking and causing problems. But I have it on there very strongly now. Then I checked timing. Timing is probably not the issue as I had it set very conservatively before proper tuning. It's at like 15-17 btdc.
I took it out for another spin. Everything seems good until all the sudden the boost gauge doesn't read boost. Pull over and now the pipe just before the maf is popped loose. I'm thinking the maf is just really slick and difficult to grab on to. I'll use multiple clamps and hopefully this will be an old issue.
Just to kind of put me at ease. What does it sound like when the ecu pulls timing? What this felt like to me was first I'm accelerating on boost just fine, then all the sudden no more pull and a change in motor sound. I suppose it could have been the air coming out of the pipe just after the maf and then the richness in the engine. But I just don't want to be scared to run the car.
This morning I adjusted one of my IC pipes. It looked like it had been forced pretty far from where I installed it. It was the pipe right after the maf. It's possible that on boost air was leaking and causing problems. But I have it on there very strongly now. Then I checked timing. Timing is probably not the issue as I had it set very conservatively before proper tuning. It's at like 15-17 btdc.
I took it out for another spin. Everything seems good until all the sudden the boost gauge doesn't read boost. Pull over and now the pipe just before the maf is popped loose. I'm thinking the maf is just really slick and difficult to grab on to. I'll use multiple clamps and hopefully this will be an old issue.
Just to kind of put me at ease. What does it sound like when the ecu pulls timing? What this felt like to me was first I'm accelerating on boost just fine, then all the sudden no more pull and a change in motor sound. I suppose it could have been the air coming out of the pipe just after the maf and then the richness in the engine. But I just don't want to be scared to run the car.
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C-Kwik
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A small spark is better than no spark. If the spark is blown out by boost, you get no spark, which results in a complete misfire. A small spark is much less likely to misfire than no spark. If you are that concerned about keeping the gap more reasonable, then get an ignition amplifier and/or a stronger coil. My car has been running fine a .027" though.
Backed of timing will not cause such a drastic effect. You will lose some power, yes, but it will not feel like a rev limiter. Most of the time, you'll hardly feel a timing retard. It will not sound any different either, unless for some strange reason, the timing is backed so far off that a significant portion of the mixture is burned in the exhaust. And this is actually something that happens when you misfire. All the unburnt fuel and air makes it's way into the exhaust. When I had a divorced wastegate and this happened to me, I was shooting flames under my car. Scared a few cars off in the process.
Backed of timing will not cause such a drastic effect. You will lose some power, yes, but it will not feel like a rev limiter. Most of the time, you'll hardly feel a timing retard. It will not sound any different either, unless for some strange reason, the timing is backed so far off that a significant portion of the mixture is burned in the exhaust. And this is actually something that happens when you misfire. All the unburnt fuel and air makes it's way into the exhaust. When I had a divorced wastegate and this happened to me, I was shooting flames under my car. Scared a few cars off in the process.
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PMan_S13
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Haha that's awesome. Reminds me of my friends xr4ti running 25psi with a vented factory bypass valve. Every shift it made 10 foot flames out his twin exhaust and sounded like a freakin bomb went off. Really fun to drive through town.
Well what I pretty much wasted my day on was trying to fix that maf. The s14 casing pretty much was starting to fall apart. Just too britle I guess. So I fabbed up a hacked maf out of it. Since I have a safc2 anyway I was just going to do the math and add fuel. I used a pipe with 2 7/8" ID which comes pretty close. Only +1% change to be "even". Made it look kinda professional actually, but when I checked the sensor with the ignition on it was reading like 3.7 volts. Took it off an found that the little flat sensor on the side was broken in half.
Needless to say I have my orignal maf installed again...
The original problem is still there. But from what I'm hearing it doesn't seem like the ecu could be the culprit. The best I can describe is it goes from pulling to nothing and just that loud sound (kinda like what a semi makes while slowing down in gear). And plus the fact that I can feel the ignition missing at lower throttle just seems too clear an issue to me now.
If it's not fixed after I get my accel plug wires and regapped ngk plugs put in I'll come back.
But for now thanks for the help.
Well what I pretty much wasted my day on was trying to fix that maf. The s14 casing pretty much was starting to fall apart. Just too britle I guess. So I fabbed up a hacked maf out of it. Since I have a safc2 anyway I was just going to do the math and add fuel. I used a pipe with 2 7/8" ID which comes pretty close. Only +1% change to be "even". Made it look kinda professional actually, but when I checked the sensor with the ignition on it was reading like 3.7 volts. Took it off an found that the little flat sensor on the side was broken in half.
Needless to say I have my orignal maf installed again...
The original problem is still there. But from what I'm hearing it doesn't seem like the ecu could be the culprit. The best I can describe is it goes from pulling to nothing and just that loud sound (kinda like what a semi makes while slowing down in gear). And plus the fact that I can feel the ignition missing at lower throttle just seems too clear an issue to me now.
If it's not fixed after I get my accel plug wires and regapped ngk plugs put in I'll come back.
But for now thanks for the help.
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PMan_S13
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- Car: Building car -> breaking car -> fixing car -> start over
Update.
Got my plug wires and spark plugs in the mail today. Went to put in the new wires and the old ones fell apart as I took them out. Regapped the plugs and gave everything a nice coat of dylectric grease. Car ran much better and after 30 minutes of terrorizing every stupid riced out civic I could find, I am confident the problem is gone. =)
Thanks-Phil
Got my plug wires and spark plugs in the mail today. Went to put in the new wires and the old ones fell apart as I took them out. Regapped the plugs and gave everything a nice coat of dylectric grease. Car ran much better and after 30 minutes of terrorizing every stupid riced out civic I could find, I am confident the problem is gone. =)
Thanks-Phil