jproy

Ok, I am pretty stressed over this little problem.
Before I installed my supercharger back at 86000 miles the car was strong as hell and power was only as smooth as my right foot made it. Laser precise pedal inputs gave equal power outputs. Some time after the supercharger install I noticed the car would lose power for a brief moment while cruising at a constant speed within 10 minutes after startup. It didn’t matter what my constant speed in MPH was, power would drop and the car would buck for a half second, exactly like if I completely let off the gas and stabbed it back to where it was previously. I never paid much attention to it because it would only do it in the first few minutes of driving and only once. It never seemed to be a problem but that may have been masked by the increased power of the blower. I have since removed the MP62 supercharger to make the MP90 kit. I have not yet installed the MP90 because I have to go to Dallas to have the map made for the Emanage Ultimate and the 440cc injectors.

Well that brings us to now. Over the last five months the blower has not been on the car and I have been running normally aspirated. The surging(power cut-out) has not only become more frequent but is now causing serious power loss at the top end. I removed the ESM and soldered all connections perfectly. I have a fresh perfectly clean air filter. There are no DTC’s (Diagnostic Trouble Codes) nor have there been any. I purchased a new Acura/Honda FPR and installed it in place of the Comptech FPR. Still, I have the same symptoms.

As of late, when dropping a gear and dropping the hammer, the car boggs down hard and wont accelerate at all for a whole second then takes off like it should have. But sometimes, like tonight and other times, I floor it in first or second and at 6000RPM the power completely goes away like I hit the rev limiter but we all know there is not a rev limiter on this car except at 7200RPM (only the autos have a limiter at 5500rpm if you didn’t know). However, every time I floor the car, while holding the accelerator to the floor, the power comes in phases. It feels good most of the time below 3000RPM, but from 3-7K it either cuts out like I said before or it comes in in phases. I get good power, then some more, then either the rev-limiter effect or 100% power. By no means is this effect limited to a specific RPM. I have only seen the limiter effect 3-4 times but that may just be how it feels when the power goes out at the higher RPM ranges. The power loss is easiest to duplicate in 1st, 2nd, or 3rd gear. I am not in any way certain as to what the problem is and am now in the phase of replacing shit until it gets fixed. I'm very frustrated since I have no DTC’s and it is random when it happens. When it did it, it was only for a moment, but now seems to be anytime I floor it at the top end of the RPM range. I purchased a new MAP, IAT, and ECT sensors. When they come in I will put them on and see what happens. Next would be the TPS (but where do I get a good one?), then the IABCS(Intake air bypass control system), then the EGR, then fuel pump. The IACV (Idle air control valve) is working properly and couldn’t be causing this anyway. The car idles perfectly. I have searched all the surging threads and only found threads about random power increases linked to TPS and the Comptech ESM problems or FPR problems. I originally thought this was an ESM problem because I never soldered mine in but now it’s out and all connections are properly soldered.

I have the service manual and all the tools but I still want all the pro input I can get here. Anyone seen something like this before? What else should I consider replacing? I am the original owner of this car and it never did anything like this before with the same modifications for 86000 miles, NOT ONCE. This is not a “live with it problem”, but is a major safety hazard and performance problem. Basically the car is stock at the moment with only headers, UR crank pulley, CAI intake, UIM spacer, Innovative front and side mount with vac. hose plugged, and a port and polish on the UIM. I do have the Walboro 255 LPH fuel pump in the tank but I bought it new and don't think this is the problem but I can’t rule it out. I cant even begin to talk about installing the MP90 until this issue is corrected. Thanks for your time and help, Jim

rondog

iTrader: (1)

damn man, battery is connected good? Injectors are clean and proper? You seem to know alot already, good luck with it and post if you find out whats wrong man. I hate to hear stories like this.

fuzzy02CLS

iTrader: (2)

Cat converter?, Or a sensor. Doesn't sound anything mechanical.

02CL-TypeS

sounds like a clogged CAT to me

dru2

What kind of o2 sensors are you using?

dru2

I've experienced something similar to that where power was cut off within the first few minutes of driving. It was due to the Bosch o2 sensor that was connecting to the j-pipe. Soon as I replaced it with an oem sensor it was smooth sailing after that - the problem went away.

poisx7

iTrader: (1)

I think this guys are right on.

its probably something that has to do with a restricted flow.

A clogged CAT or a bad 02 sensor might be the culprit.

I also liked how u said "Basically the car is stock at the moment with only headers, UR crank pulley, CAI intake, UIM spacer, Innovative front and side mount with vac. hose plugged, and a port and polish on the UIM"

STOCK.......ohh really ?

jproy

Your right! I guess I am used to the supercharger and other parts. Sorry, i guess its not stock at all.

I replaced the primary o2 sensor 10000 miles ago. The cat is a RT7000, brand new, custom made for my car. 2.25" in and 2.5" out. I just checked it and it is clear.

jproy

The 02sensor used was the honda oem replacement part.

davepaul033

iTrader: (1)

I have been having the same problem ever since I installed the walbro 255 fuel pump. It only happen in the first 30 mins of driving and the more you drive the less noticeable it gets. Its like the fuel pump stops working in the middle of acceleration, then surges fuel back into the motor and you take off like you are launching the car.

jproy

I still have the stock pump and will probably try it before i buy the expensive parts. I really think it could be the pump. I will have the wideband on the car next week so i will see what the a/f is doing. Im installing a boost/vac gauge also but i donk think that will help here.

Kulrevon

I would say the fuel pump might be making you run rich enough to give you problems.

I would also say it could be the tps. Is the CL tps the same as the other hondas? I have never checked.

With the obd1 cars if the TPS was causing this problem your could unplug it. It would throw a code but it would run smoother. I am sure you would loose power but it is one way to test it. You could also check the voltage to see if it is linear.

I would say start with changing the fuel pump because that is free. Just labor.

jproy

I started noticing the the slight hesitations after installing the supercharger but I know others have not had the issue so I think it could be that I have a bad pump but you could be right also. I dont see how the car could get rich enough to cause a problem that would cut the power and most of the time just modulate between 50%-100% power with the pedal to the floor through the RPM range. The OEM FPR would never let fuel pressure get high enough regardless of how much pumping the fuel pump did. Any extra fuel that would bring the fuel pressur higher is redirected back to the fuel tank. It would only drop pressure if the pump stopped. Its most noticable in the gears where the tach can sweep the fastest, like 1-2-3 gear. You can feel it in all gears though. I forgot to mention that I now have 111,000 miles on the car now.

Kulrevon

Either way if its making you run rich or if its cutting out. I would say to pull it out and throw in the stock one.

And I still would check or replace the tps. I have an extra CLs throttle body and VSA throttle body. Thats if you want a used one. I would see if they are the same as the other hondas. I actually have just a spare tps in my center console.

If you look up acura tl tps on ebay you will see omni. He says they are all the same.
http://cgi.ebay.com/ebaymotors/.............

zeta

iTrader: (1)

When I removed my blower so that the dealership could replace my clutch, the cars power/driving dynamic had some how changed slightly. Of course, without the S/C'er there was diminished power, but the car still felt strange. It's hard to explain, but the car felt sluggish but not to the point where it became an issue. Of course, all was well once I placed the S/C'er back in

Perhaps, the interaction of the CT fuel pump, CT FPR and cooler plugs had an affect on how the ECU did its thing, less the S/C unit.

I have always had that early stumble in power shortly after start-up; however, it would not last and was not as severe as you mention. I still get the stumble to this day; however, I find that if I let the car warm-up a bit upon the mornings cold start, the stumble is very slight or non-existent the majority of the tme. There have been other threads that attributed the early stumble to the loop change over, IIRC.

Try the oem fuel pump replacement, as mentioned. Might also want to try a set of oem plugs as well. Then all those components will be back to stock too.

Good luck.

jproy

We hooked it up to a Honda scan tool and looked at all funcitons in real time. I will elaborate. I am changing the fuel pump back to stock and see if all is back to normal. I will explain all later. Jim

poisx7

iTrader: (1)

interesting, never thut running reach could make it do that.

seems to me like a defeciency.
I was really hoping it was the CAT.

keep us posted.

jproy

Here is the short story. You guys are going to give me some shit for this.....drum roll....LOW OIL!!!! Yeah, bottom line, I was almost 2qts low on oil. Took a look at it after the stock fuel pump made a marginal improvement in only low end power and sure enough the stick came back out clean like before I put it in after cleaning it the first time. I added almost 2qts of M1 and took a test ride. Wooooh, forgot how fast the car is. The thing screems and broke em lose in second just from the power as I swept past 6K rpm. FUN!

It turns out though I did figure something else out which is also very important. The 255 Walboro should not be run with the stock FPR. It seems the stock FPR does not have large enough plumbing to return the unused fuel back to the tank without significantly increasing the psi on the injectors. The long term fuel trim was at -14% and the short term was at about -17%. Way bad! The car runs perfectly now but I am going to have a compression test done tomorrow or thursday so I know what I am working with before the MP90 goes on. I will get a larger 1:1 Areomotive FPR to use with the RC440cc injectors.

Should have seen my face when I pulled the dip stick out and it was as clean as when I stuck it back in. Not a smidge of oil on it. Thanks for all the help but this sucker screems now.

Two big lessons learned here,

1. Walborow 255 fuel pump should not be used without a high capacity FPR.

2. Check the oil!!!! I have run M1 5W-30 since the first oil change at 7000miles. 6000miles ago I put 5W-20 M1 in and have no leaks but it just burnt out some how. I will now watch the oil like a hawk, get the compression test and change back to 5W-30 ASAP. I will let you guys know how the compression test comes back and what the oil consumption is like with the 5W-30

Allout

Good to hear you've got it figured out. You may want to make sure your PVC valve is clear and free also. A compression test will give you some info. You may get more info out of a leak down test.

It's pretty amazing what the car runs like with and without VTEC.

jproy

Im on it. Waiting for the quote now.

EL19

iTrader: (4)

My car was doing that when I was boosted. In my case it was the FPR.

Good one figuring it out but now I have to take my 255 out! My mechanic NVA AV6 left my 255 in when taking out my SC. Time to either take the 255 out or get a new FPR. Thanks

typeR

crap i was just about to give my stock low oil statement ! at first itll happen when turning later as it gets lower anytime vtec change over occurs

poisx7

iTrader: (1)

good to know u figured it out.
But, i also figured since u know ur shit, u were going to figure it out one way or another.
Good luck and thanks for the diagnosis.

so the question is what makes ur oil burn that fast ????

jproy

I am going to write a long analysis and conclusion about this whole issue after I get the leak-down test performed. I know exactly why the people with the Comptech FPR have issues at startup and sometimes during normal operation. I have figured out quite a lot and will share it all soon. The major issue at startup is that the fuel pressure is below 40psi, usually at about 33-36psi at idle and the ECM must significantly increase the fuel trim to get to stoic. At cruise the fuel pressure is still not in the specs the ECM wants to see either. The pressure is much higher than the settings the ECM wants to see with the stock FPR. So the Comptech FPR wreaks havoc with the fuel trims on the ECM and causes all kinds of power fluctuations since it has to go from + to - fuel trim with every opening of the throttle. The ECM is designed to see minimum idle fuel pressure of 41psi and a max of 54psi at WOT. In a dyno with the Comptech FPR I was once able to get the idle fuel pressure so low, about 28psi that the car would not idle. It would stall and die without a little throttle. That means the ECM was unable to increase the fuel trim enough to make the car get enough fuel to run but the dyno pulls still showed me at 11:1 or richer at the WOT pulls with the blower and a perfect 14.7:1 without the blower with the 8:1 Comptech FPR and Walboro 255. Unfortunatly, it is much more expensive to go the rout I have taken using the larger injectors and a piggy-back computer to compensate for duration along with a tune.

Comptech way of fuel control;
Walboro, ESM, and 8:1 FPR, Causes crazy fuel fluctuation and is very inaccurate. That’s why you always hear people here talking about how you would never see this setup on a factory car with a blower or a turbo. FPR($300), Walboro ($100), ESM($100), TOTAL $500 for fuel management.

My way(The way a professional or car company would do it);
Larger injectors capable of spraying enough fuel at 55psi to make 500 shaft HP($785), Walboro 255LPH pump($100), High-quality 1:1 FPR hoses and fittings ($300), Emanage ultimate ($500), Tune ($300-700), ECM wire harness ($210). This will give me precise, exact fuel metering every time with little to no fluctuations and is at a safe fuel pressure plus I get to precisely control some other things on the motor. TOTAL minimum $2,195 for fuel management.

So it’s easy to see why Comptech did what they did and it is fine so long as you don't want to use anything more than the HBP. Some people have trouble with even the High boost pulley though also. The engine gets way lean at VTEC and IMRC engagement and there is no way to add fuel with the Comptech kit at those intervals without making the whole power band fatter, unnecessarily richer. The Emanage will allow me to do that. I didn’t mind spending the money to make it work right because I can take most of it off and use it on another car if I want to move on. There will be others. What I can’t, I can always sell at a decent price and get what I need for the later, larger projects.

I will be changing to a large high quality 1:1 FPR so I can use the Walboro 255LPH pump and maintain the stock fuel pressures at the same ratio as the stock unit but with much better fueltank-return flow rates. I need to do this obviously because I will be using the RC 440cc injectors and want to run the stock fuel pressures. 75+psi is too high for comfort and 110+ psi is insane with any injector. I know they start to lose efficiency at about 75psi. So, I need the Walboro 255LPH to get enough fuel to the RC440’s even if they will never see more than 55psi.

I will be honest with you guys and tell you I neglected the hell out of the car over the last oil cycle. I have used 5W-30 M1 since the first oil change and at 104,000 I switched to 5W-20. I don’t know if the lighter weight would have increased oil consumption or not. However the big thing I have to admit is, I have not checked the oil since the change at 104K and I am now at 111.7K. So I went almost 8000 miles without changing the oil or even checking it. I was normally aspirated for all of that time. Lesson learned, CHECK YOUR FRICKIN OIL REGULARLY! I know, I should know better. The OEM interval is 7,500 miles so I still think I may have a critical oil consumption problem internally but we will know soon from the leak-down test. If I have a big problem on the inside I will put the MP90 on hold, pull the motor, rebuild to 3.5L specs, then put the MP90 on. I hate to admit it, but I really won’t care if the motor is due for a rebuild. It would be fun. Jim

poisx7

iTrader: (1)

I like to read notesof ppl who like to diagnose, analyse asnd share knowledge.
seems very educational
Thanks 4 the good work.
I hope ur engine is still healthy otherwise its good to have $$$$$( may the Project go OOOOOOOOOnn)

flint

iTrader: (2)

Thats a lot of good information. I have been getting some detonation lately after vtec engages through redline running the SC and HBP. Sounds like I am probably running lean. Thoughts?

Oh and I hate that cold stumble for the first minute or two of driving now that its turned colder!