Stevey629

OK, here we go again, I have posted about this before, but I havent gotten responses either because I havent given enough information, or dont know which information to provide. Please feel free to ask if you need more information about anything I have done to the car. In any event, here is my list of mods:

MOTOR:
new cryo'd 2nd stage street ported motor
upgraded oil pedestal
silicone vacuum hose job
stock turbos and stock ECU

INTAKE SYSTEM:
K&N drop in filter w/stock pipes, bov and intercooler. New crossover pipe couplings (the 2 that affix to this pipe only).

EXHAUST SYSTEM:
Stock DP (precat still affixed), Stock midpipe (main cat) and an Apex'i N1 Catback system.



My question is why my car feels so unresponsive as stated in the title. I know there is a certain degree of compression loss with a new motor. My cars symptoms are a slight vibration as my revs make their way back down towards idle, and of course on their way up. this "vibration occurs between 0 RPMS up to about 3 RPMS, and then the car feels smooth above that, but unresponsive. Unresponsive meaning when I gas it (maybe 50% throttle or so), it feels like there is no power, or a very slow change in RPMs as they rise. I havent gotten on it hard due to worry about the new motor (no revving above 4500), but I can feel that if I gave it more gas it probably wouldn't do much else aside from blowing more fuel than it already does. Idle is stable, as I have already checked the MAP sensor and idle control plug was actually unplugged. I forgot to put it back in after I lost it taking the manifold off to change the injectors. Which brings up a new point: When I first got my motor back, I was spitting flames, due to a stuck open injector(s). I replaced the secondaries, and sprayed carb cleaner on the primaries, and it helped a lot, but it still feels slow. I am assuming that it could possibly be an ignition problem, so I took the liberty of changing plugs, but consequently not much changed. Could a coil pack(s) be bad? Is this something that occurs regularly? I dont know if I am leaking boost because I dont have a boost gauge. I am thoroughly confused as to why it feels essentially NO fun to drive the car. Its hard to keep it driving smoothly, and it doesn't want to rev up smoothly and quickly. What do I do from here? someone point me in the direction to fix my car, or check to see what could be causing this UNRESPONSIVENESS, and we can work from there. Thanks for any help in advance, I'll work with you guys as best I can. Im really new to the rotary world, and I'm just starting to taste whats involved in making this car run.

spurvo

Ouch. You really DO need some kind of boost gauge to see if your turbos are working (it REALLY sounds like they aren't). I have also been following 93BlackFD's deal with an engine builder with the same vibration problems you are describing, you are aware of that?

The most I can say about responsiveness on a new engine is mine was a little sluggish for the first 100 miles. After that, it would accelerate responsively. I found that it felt like it had no trouble accelerating as much as I gave it throttle, like a "one-to-one" feeling. This only means that if I gave say a 1/16 pedal input, the car sped up kind of that much as well. If I gave slow throttle input, it would slowly push me into the seat. Quick shove of the pedal gave sharp push, right away. Almost all of this responsiveness during the break in was due to the turbos, as at least mine any way will give a helping hand all the way down below 2000 rpms. I kept the rpms low like the builder suggested, so I can't say anything about responsiveness above 3000 rpms on an engine younger than 1000 miles. It definately sounds to me like you have a problem (duh, right?), and I would start by asking if your turbos are giving ANY positive pressure at say 2500 rpm. A boost gauge will allow you to determine this. Go to the local parts store, get a simple vacuum/boost gauge, hook it to the intake manifold (the little tube on the passenger side of the upper intake manifoldwith the cap on it), run the hose up under the wiper blade and use that to hold the gauge. Then drive it, get it up to 2500 rpms in third, and gently but firmly apply throttle. The gauge should track your foot's motion EXACTLY, going from roughly 10 inches vacuum to a positive number. Stop at 5 psi, positive pressure, if you are actually making boost. Only go up to the boost breifly to test the system, then let off. Once you've done this, we can give suggestions as to what the engine is doing.

A turbo car is harder to diagnose soft acceleration problems, as it might be the turbos, OR it might be the engine. N/A engines with soft acceleration are easier.

Hell, you may just have the double throttles staying closed, which limits acceleration REAL nicely...

Let us know

BigIslandSevens

iTrader: (4)

Street ports and stock ECU's don't mix very well. The timing needs to be adjusted for the new engine. ( this is not possible with the stock ECU) That's my 2 cents worth of babble.FWIW: Have you done a compression test since the injector problems?EDIT: Also for the new ECU I would recomend something like the M2 or PFS(not the power FC with the amount of mods you have) I would also recomend at least a good DP to help things flow a little bit better.What are the plans for the car?( helps determine which ECU to get)

SkywarpR

I was also under the impression that you should upgrade your ECU when porting your engine. However youcan rule out M2 their website reads "We do not offer this service for vehicles equipped with automatic transmissions, or ported engines." I am in the process of having my engine ported, my only other mod will be a downpipe initally. I will be running a Power FC. I chose the PFC because it can be changed as I add more upgrades.

voodooracing

might want to check your compression... even with stock ecu, ported motor, this sympton should not be obvious

Stevey629

thx spurvo. Commin through again as always. Ill try the boost gauge thing, so just get a cheapie from the parts store? NE ways, is it possibly a spark problem? or is it most likely the turbos? I just had them rebuilt around 500 miles before the motor blew, so Im hoping that theyre going to be new, but with these things you never know. Thx for the responses guys, unfortunately I dont have the funding for an aftermarket ECU, and from what my rebuild guy told me, I can run my stock ECU with the port. I just cant flow too much, as I will start to lean it out. His suggestion was to keep the exhaust restricted until I do get a Power FC or similar ECU type system.

G Goodman

Don't know if this helps but have you tried resetting your ECU? My car was in storage for a while and when I got it out it acted somewhat like you are talking about. I reset the ECU and no more problems.

Stevey629

um, how do you reset it?

clayne

Stevey,

You've really got to outfit this engine with the proper diagnostic equipment.

First step: boost gauge.
Second step: Water temp gauge.
Third step: Apex'I Power FC.
Fourth step: Tuner.

There's really no way we can figure out what is wrong with your engine (if there is anything wrong at all) without having the appropriate equipment to gather valuable data.

You have a ported engine. The stock computer is not designed (although it WILL run) for a ported engine. There is nothing we can do about this. No super spark plugs or looking at the stock ECU differently will change the fact that your ported engine has different flow characteristics than a non-ported one.

About the only possible thing I can think of is your O2 sensor. But if it was working before, it should be working now.

Until you get a tuner to modify the fuel and ignition maps based on your porting and mods (requires Power FC or equiv.) we're just shooting at things in the dark.

Stevey629

I know I need to get these things to obtain vital information from my motor, and turbos, but this is precisely why I was asking these questions in the first place. Has anyone seen this type of problem or familiar with it enough to diagnose it without saying I need a fuel computer? I understand that the stock ECU doesnt recognize the new amount of air flow, but rough vibrations up through 2k shaking the whole car side to side (when cold)? Will not having a fuel computer really make the motor run this rough? Have trouble idling below 1k? Glowing red interior pipe of muffler? Extremely unresponsive? If so, I have no further questions until I get a boost gauge or/and Power FC, because ideally I would absolutely love to have one of these, its just that I don't have anyway of affording one of those at least for the time being. Consequently, if I can fix the way its running (just smooth it out), by then I should be able to get my hands on a Power FC, which will hopefully cure all these problems, and take full advantage and properly control all that untapped power under my hood. I know this sounds terrible either way I say that I just want to make the damn thing run without an upgraded ECU, but I am strapped for cash for one, and for another am convinced that it cannot possibly run this horribly on the stock ECU. But then again, I learn new things everyday on this forum, so ya never know. I hope some of you understand where I am comming from. Im trying to avoid sounding too naive here, but I guess I've already done that. Thx for the help with this guys.

Stevey629

Oh, and while Im on it, would a hyper ground system or something like that help? All my gauges, lights, etc. flicker when I get idle bumps or hiccups.

911GT2

Can't hurt to do it. But the idle hickups could be due to the loss of electrical power, as opposed to the loss of power being due to the hickups. Either way it can't hurt to re-ground everything.

rx713bt

iTrader: (4)

If the leading plugs aren't firing and the trailing plugs are, then it will feel slugish like you mentioned.

93BlackFD

heh, you can't afford a powerFC now, i hope you can afford a new motor later ;-)

jpandes

FWIW, My car felt sluggish suring my break in period too. Think about it, you're not supposed to really get on the gas hard at all for the first 500-1500 miles. That means little to NO boost.

The street port also robs you of alot of your low-end power, basically the power band that you are supposed to be driving in during break in.

Now, for the vibration issues. I didn't have that problem with my new motor. I read 93BlackFD's post about his motor vibration issues, it wasn't good.

zkeller

iTrader: (47)

I'd make sure that the double throttle is functioning properly. Take a look into the throttle body and make sure they are open when the car is not running. You will have to look past the throttle butterflies. The double throttle is actually in the UIM. The ECU sends a signal to the solinoid to close them when the predetermined conditions are meet such as during warm up. Normally they are open. If you disconnect the vaccum line from the double throttle actuator they should stay open all the time. if not they may be sticking.

Check the easy stuff like this first. I had this problem on an Automatic that I just rebuilt.

zkeller

iTrader: (47)

I agree with RX7bt. If the trailing are only firing it will feel like the timing is way retarded and will cause a vibration like feel and absolutly no power.

Stevey629

is there someway to figure out whether or not only the trailing ones are firing? Could it be that the coil pack(s) are bad? does this happen often? what else should I check? Thx for the suggestions, very seriously appreciated. And zkeller, I dont quite understand what the procedure is to check if the double throttle is open or closed. So are you saying I should just disconnect the hose to make them open all the time? that way i wont worry about them sticking closed?

zkeller

iTrader: (47)

As far as the double throttle control goes, They are always open unless the ECU pushes them closed. Just remove the vac line from the actuator near the throttle body and then they will not respond to the ECU. But, make sure they are not mechanically sticking closed. Hell, remove the butterfies from the intake! You can remove the vac lines associated, but leave the solinoid electrical connector connected.

Bad lead coil packs are common, but they usually do not die completely. they will show signs of ignition breakup under high RPMs and boost.

Take the leading out and look at them. You can also remove the trigger wire from the trailing coil packs and see if the car runs. it will run suprisingly well w/o the trailing if the leading are firing. :>). You could also pull the fuel pump fuse and remove a leading plug, connect it to a leading plug wire, ground the threaded part of the plug and crank the ignition to make sure it is sparking. I use a jumper cable to ground the threaded part.

Also check to make sure you have the coil wiring harness oriented the correct way, with the connector and wiring coming out the front of the engine. Make sure the crank trigger pickups are plugged in correctly.

is there someway to figure out whether or not only the trailing ones are firing? Could it be that the coil pack(s) are bad? does this happen often? what else should I check? Thx for the suggestions, very seriously appreciated. And zkeller, I dont quite understand what the procedure is to check if the double throttle is open or closed. So are you saying I should just disconnect the hose to make them open all the time? that way i wont worry about them sticking closed?

Stevey629

great suggestions, Ill give them a try, only if I may ask again, sorry to be so understaffed upstairs about the ignition, I just dont know what is right from wrong being that its all hooked up already. As far as Im concerned, it all looks fine to me. The wiring harness for the coil is what is in question or reference here. Where exactly is this harness located, and how will I know if its wired the proper way? And the crank trigger? Where is this? and how will I know its hooked up the right way?

another thing regarding the double throttle. This is the one that is inside the UIM correct? Anyways, how will I know if its stuck closed? from what I remember last time, I could move them open and closed with my hand, last time I had the thing off, but is there some possibility that they could still be mechanically stuck? If the butterflies seem to work mechanically, then assume that the actuator is broken, or the vacuum line is hooked up to the wrong place or something? Anyways, thx again, this is a humongous help.

Stevey629

Would it be necessary to just replace all of the coil packs? Seems a bit much, but how will I know what a good spark is from a bad one? Even after I do the test?

Stevey629

^

Stevey629

Update: Still no boost gauge, and no compression test yet. Tried some other stuff, heres the results.

ok, I removed the double throttle vacuum line, nothing changed. It seemed to be about the same. I noticed that the actuator also pulls it when I start the car cold. The butterflys seem to be in working order. I switched the wastegate plugs, which are the two olive green ones right behind the vacuum chamber near the alternator. Theyre the same size, color, and both fit either way. Maybe they got mixed up. I noticed a bit more of a spool sound, and the BOV seems to be louder. I cant really tell with RPM response unfortunately, and due to the fact that I dont have a boost gauge yet, I really dont know where else to look. When I was switching the wastegate plugs however, I noticed a stray wire just "chillin" in the engine bay. it was touching the top of the motor, and when I moved it, I heard something like a feint sparking or ticking sound comming from near the coolant overflow neck filler. Everytime I touched the wire to the block (grounded it) it made that noise. I wish I could get a picture of it, but the wire is so far down that I cant get a clear shot of it. Anyways, Im wondering if Im having grounding issues or electrical problems, and hence its causing this poor response and poorly running car. what I think I need is someone to just overlook every wire and sensor in my car and diagnose. Im getting way too tired of trying to figure out what the problem is. It could be so many things. Im gonna get a boost gauge ASAP, and a water temp just to be safe, but until then, I guess Im venting cuz I have no idea what is wrong with my motor.

james n gantt

I have a jacobs igintion and it burned out 2 primary coils before I changed to a turbo 2 primary coil. The best way to see if your leading coil is burned out is to pull the leading plug wires off the sparkplugs and see if the car runs any different. When my leading coil was out the car would start , idle and run with no problum it even would boost higher and faster then wnen it workrd correctley {the fule mixture was all burning in the exhaust} but there was no power and trying to accelarate caused the engine to bog then pick up rpm very slowly.

Stevey629

is it okay to do that? I mean, of course dont run the hell outta the thing, but is it really okay to be pulling the plug wire off and just drive it like that? And there is one coil for the primary 2 plugs, and another coil for the 2 secondarys correct? How much does one of these things generally go for? I am leaning towards this being ignition related, and praying its not turbo related...once again, I need a boost gauge to be sure. Could that loose wire under my hood be the culprit? Its a spaded clip, looks like it hooks up to a spade (duh). Its a red wire with a blue stripe, and its located towards the front side of the UIM, under the waste gate plugs. I changed the ground wire from the UIM to the chassis, not much of a difference, but I can't tell since my car is running so terribly to begin with.