99lspwr

My car is a 94 civic with a sohc/greddy turbo setup...Its been together for a few months with no real problems...However recently I found that after driving/boosting for 20-30 minutes, I have a low rpm (idle to about 2500) misfire after taking off from a complete stop..The misfire is not there until the car is driven for at least 20 minutes...My plugs look good, and my wideband looks good when this misfire happens, so I believe it may be ignition related, not fuel....Anyone ever have any problems like this??????Thanks in advance for any help...

platinum00

when is the last time you changed your cap, rotor

that would be a cheap place to start.

m R g S r

I had this problem....with my untuned turbo gsr afc hack setup. . .plug gap was too large, only happened after it was running for a while. . .

99lspwr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by platinum00 &raquo;</TD></TR><TR><TD CLASS="quote">when is the last time you changed your cap, rotor

that would be a cheap place to start.


</TD></TR></TABLE>

Yeah, I checked all ignition parts as well as replacing them a short time ago, and everything still looked ok...

99lspwr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by m R g S r &raquo;</TD></TR><TR><TD CLASS="quote">I had this problem....with my untuned turbo gsr afc hack setup. . .plug gap was too large, only happened after it was running for a while. . .</TD></TR></TABLE>


Plugs are gapped at .30, and they looked fine as well...I never expierenced low rpm misfires because of improperly gapped plugs, only high rpm...Oh well maybe I will try to gap them at .27.................Thanks for the suggestions though..

99lspwr

p.m. bump for me!!!!!Anyone else???

99lspwr

Tuesday a.m. bump!!!!

200cs

I had this problem with my 2000ITR before it was boosted. It was the stock coil heatsoaking and failing. I replaced it with a Jacob's ignition system and MSD cap and 8.5 mm plug wires. I used a stock rotor. Good luck!

99lspwr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 200cs &raquo;</TD></TR><TR><TD CLASS="quote">I had this problem with my 2000ITR before it was boosted. It was the stock coil heatsoaking and failing. I replaced it with a Jacob's ignition system and MSD cap and 8.5 mm plug wires. I used a stock rotor. Good luck!</TD></TR></TABLE>


Funny you mentioned that, I just switched mine for a known good one last night and will give it a try to see if it helps any....

200cs

you can also check the resistance between the primary and secondary windings of the suspected coil. if they are even slightly out of limits, replace the unit. My ITR manual gives the following values if you are interested:
Primary Winding Resistance (The two small positive and negative wires feeding the coil) 0.6-0.8 ohms.
Secondary Winding Resistance (The Positive feeder wire to the plug wire output of the coil) 12.8-19.2 kilo ohms.

I have replaced more ignition coils in my life due to drivability problems than any other unit. This includes carb tuning and the like. Factory coils just do not seem to last like aftermarket units do. I have been very happy over the years with Jacob's products even if they are not as popular with the import crowd. MSD also makes high quality units that are far better than oem especially if you by the exciter box like an msd 6 to go with a new coil. Let me know if this fixes it.

Syner-G-Racing LLC

I have the exact same symtoms with my turbo setup except the misfire happened at cruise speeds after about 20-30 minutes of driving. its really random though. I havent solved it yet. what type of engine management are you running by the way. Ive been leaning toward a bug in my engine management (hondata/zeitronics)

200cs

believe it or not, I am using the AFC hack to fuel for the time being. I live in a plug to test area for emissions and cannot get rid of the OBD2 and stay legal. I have considered getting uberdata or hondata and swapping computers at inspection time but do not like the idea of not having a knock sensor when using a p28 ecu and from researching, I do not think I will be completely happy with either set-up .
My plan for the year is to buy an msd btm to retard timing when in boost (the car is doing it for me via the knock sensor but is pulling out about 20 degrees which I think is too much) and keep the AFC for fueling. Other than cold start issues with the bigger injectors, the car really runs good-just not good enough...
At the end of the year, I will probably by an AEM system this seems to be the best out there by far and has been recommended several times even for OBD2 cars.

99lspwr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 200cs &raquo;</TD></TR><TR><TD CLASS="quote">you can also check the resistance between the primary and secondary windings of the suspected coil. if they are even slightly out of limits, replace the unit. My ITR manual gives the following values if you are interested:
Primary Winding Resistance (The two small positive and negative wires feeding the coil) 0.6-0.8 ohms.
Secondary Winding Resistance (The Positive feeder wire to the plug wire output of the coil) 12.8-19.2 kilo ohms.

I have replaced more ignition coils in my life due to drivability problems than any other unit. This includes carb tuning and the like. Factory coils just do not seem to last like aftermarket units do. I have been very happy over the years with Jacob's products even if they are not as popular with the import crowd. MSD also makes high quality units that are far better than oem especially if you by the exciter box like an msd 6 to go with a new coil. Let me know if this fixes it.

</TD></TR></TABLE>


I drove the car last night with the "known good coil" that I switched, and it seemed to solve the problem...I drove the car at least 25 minutes with absolutely no low rpm misfire....I will drive it again tonight and see if its cured for good.....Thanks for the voltage readings...I will try them anyway to see if is in spec..

Flr Power

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 200cs &raquo;</TD></TR><TR><TD CLASS="quote">Factory coils just do not seem to last like aftermarket units do. I have been very happy over the years with Jacob's products even if they are not as popular with the import crowd. MSD also makes high quality units that are far better than oem especially if you by the exciter box like an msd 6 to go with a new coil. Let me know if this fixes it.

</TD></TR></TABLE>
Mine is still going strong in mi 1990 Civic. Yes, original coil and igniter.

99lspwr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Flr Power &raquo;</TD></TR><TR><TD CLASS="quote">
Mine is still going strong in mi 1990 Civic. Yes, original coil and igniter.</TD></TR></TABLE>


I never really had a problem with too many factory coils either...I thought since mine was 12 years old along with using the msd unit, it may have put alot of strain on the coil...

200cs

I noted most of my problems with factory coils after I started adding performance parts and upgrades. Most factory ignition systems are designed for normally aspirated engines and the coils are only designed to put out around 30,000 volts and fire each cylinder one spark per combustion revolution. Aftermarket setups like Jacobs or MSD usually use 50 to 60,000 volt coils with exciter boxes that fire several times per combustion revolution. This gives greater fuel burn and increased power. It has been my experience that they work extremely well and the power increases are noticable right away. However, I am sure there are exceptions to evey rule and I wont say a factory set up is not good enough, i just prefer aftermarket based on my own experience.

liam821

My car does this when i start to foil my plugs. Even tho they might look okay, you might want to try a fresh set and see if that helps your problem.

liam

99lspwr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by liam821 &raquo;</TD></TR><TR><TD CLASS="quote">My car does this when i start to foil my plugs. Even tho they might look okay, you might want to try a fresh set and see if that helps your problem.

liam</TD></TR></TABLE>

Yeah, I would have not suspected the plugs because of the condition that they appear to be in....They are only about 5000 miles old or so though..I am using (7) heat range plugs gapped at .30 Any suggestions??

g2turbo

I had the exact same problem with my turbo b16 on hondata. Never really solved the problem. I ended up selling the block to a friend and he is having the exact same problem. I think mine is related to the tune though because I put my map in his computer. It was really weird.

200cs

Hi Liam, Do you still run the AFC Hack?

99lspwr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 200cs &raquo;</TD></TR><TR><TD CLASS="quote">Hi Liam, Do you still run the AFC Hack? </TD></TR></TABLE>

I would venture to say he does not..