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View Full Version : Idles fine, Misfires upon acceleration



bocochoco
06-12-2009, 04:20 PM
I was on my way to a camping trip I had planned for 6 months and was 20 miles away....next thing I knew it took 1 1/2 hours to get home :093:

I am lost here guys. My '94 2.4l 4g64 was driving fine. I pulled up to a light and when I tried to take off the car starting misfiring BADLY. I pulled into a parking lot and it was idling just fine.
I decided I didn't have the money for a tow so I drove it home...at times I could get it over 50mph going downhill but uphill climbs killed me.

It idles at around 1000 but if I accelerate too fast the RPM's drop and I get nearly zero power. Sometimes I was able to get it to 1500 and SLOOOOWLY climb.

I checked the jumper to my fuel pump and it worked fine.
Also I just got gas...maybe BAD gas?
And just this morning I removed my horn fuse because I have a short in the steering wheel ...could that control something other than horn? I put it back in but it didn't do nothing.

I recently last week installed a new distributor and it ran fine until now..Must get spark since it idles fine.

ANYBODY HAVE ANY IDEAS???

starh4x
06-12-2009, 05:12 PM
is your fuel tank always close to empty like mine? maybe you have condensation in the tank?

DOHCstunr
06-12-2009, 05:21 PM
sounds like a major post mas vacuum leak.

Is your intake manifold cracked?


edit: nevermind you have 7g. it would take an act of god for that to happen.


check all your vacuum hoses and intake track for leaks

skrap
06-12-2009, 06:44 PM
plugs and wires... they act really funny when they go bad in this car. When did you get them replaced last? Also could be fuel filter and or clogging injectors... when is the last time you used injector cleaner?

mko
06-12-2009, 06:55 PM
Is the Check Engine Light on? Hows the front O2 sensor?

starh4x
06-12-2009, 07:59 PM
Where is the fuel filter on an 8g ?

bocochoco
06-13-2009, 03:16 PM
Lots of good things to check....I used some gas treatment 2 fill ups ago which should have helped remove condensation...The car was sitting for 3 months due to a no spark condition but since I replaced the dizzy it started fine. Although now after this problem arose it has to crank quite a few times before the engine turns over. Still Idles ok but no accel.

I know I had a small leak on my intake manifold....sounded like a classic VW bug. Unless it sucked some gasket in I don't think there is much of a problem there.

I have checked my hoses and found nothing obvious although I was trying to turn over the engine at one point and my hose to my pvc valve popped out loud as hell. This never happened before but I figure back pressure.

Check engine light has been on since forever. It comes and goes. Car actually accelerates better when it is on. When it is off sometimes it would bog out on me. Intermittently. Now it is a permanent situation. Maybe whatever was causing this to happen finally shit out for good....

Should I take it in and pay for a diagnostic code read?

diablos991
06-13-2009, 03:28 PM
You should be able to get the code pulled for free at a local auto parts store.

mko
06-13-2009, 03:37 PM
You should be able to get the code pulled for free at a local auto parts store.


He has 94 = OBD1.5 = No good for scanning. Im pretty sure it will be the front O2 sensor, cuz my car did the same thing when it went

bocochoco
06-13-2009, 04:11 PM
ARGGG now it wont even start.....Hey I'm wondering if the dizzy I bought is bad...
Advanced auto parts and refurbished...

Galanttuner10
06-13-2009, 10:49 PM
the distributor might not be bad.. did u make sure everything was lined up the exact way it was before??? did you replace the rotor as well? and did u do the wires as u might have mixed up the wires?

shots in the dark here but things you should check

Way Fast Galant
06-14-2009, 01:24 AM
i had the same problem years ago, kept driving it and it just died one day. turned out to be my coil in the distrubutor. mechanics at the time said its cause you have a leak on your air box, one said the cars got power compared to a honda. then i die on the side of the highway to find no spark LOL. but take a look to that, and get your codes checked.

panda
06-14-2009, 03:49 AM
hahaha damn man you got a whole list of shit.

but i figure i will give ya some advice

a 02 sensor would make a bad idle so that wouldbe the last on the list..


for a bad ignition replace and check gap on spark plugs replace wires

check your timing with a timing light cause your dizzy might be out

gas wouldnt be a big issue cause if it cranks then nothing should be clogged,

check for a vacuum leak get you a can of carb cleaner crank the car and spray the intake lines and see if the idle gets erratic



pretty much what it sounds like is your ignition system needs to be attended to..

panda
06-14-2009, 03:53 AM
mechanics at the time said its cause you have a leak on your air box, one said the cars got power compared to a honda.

what did he mean by that lol

RedGalant2k1
06-14-2009, 08:29 AM
ALWAYS check what was just replaced first. If the issue ESPECIALLY is only since the repair that was performed. But I'm surprised that no one has suggest the fuel injectors. They could have a ohm resistance problem when under load that causes or allows for poor acceleration. Pretty common problem actually...

Are there are rotten egg smells or anything else?

bocochoco
06-14-2009, 02:02 PM
Hmmm....actually there is a bit of an odd smell at times. Almost like a weird gas smell but not quite. What could this mean?

I'm pretty sure I installed the dizzy correctly and the wires should be right 4 3 2 1

Rotor and cap was replaced...also a new coil came with the new dizzy so unless somethings causing it to fail I don't think that is it.

I shall try the carb cleaner technique. I forgot about this one. Although not sure why a vacuum leak would cause a complete start failure.

My injectors are getting voltage...although I am not fully sure how the signals interact with my ECU.

Hey that's a thought...ECU failure? I hear it's common to have a capacitor leakage on this car melting the board and causing shorts.

Also I noticed my cat sounds louder than usual....like obvious loud muffled humming. It does not get red like it is clogged and I have exhaust out the tailpipe...until this happened I never had this sound either

Oh also it happened the day after I brought it to pepboys since the were only ones open at the time to give me an oil change....used high mileage 75K+ oil.

kamenfaiz
06-14-2009, 04:40 PM
rotten egg mean the cat is bad

Galanttuner10
06-14-2009, 11:50 PM
i would go through everything possible because its funny how many times its a little thing that causes these issues.. i hope its not the ECU tho.. injectors are a possibility

on a side note.. i recommend doing your own oil changes, but they shouldnt be messing around in the bay or with anything that could be giving you any issue like this i hope

RedGalant2k1
06-14-2009, 11:59 PM
Hmmm....actually there is a bit of an odd smell at times. Almost like a weird gas smell but not quite. What could this mean?

I'm pretty sure I installed the dizzy correctly and the wires should be right 4 3 2 1

Rotor and cap was replaced...also a new coil came with the new dizzy so unless somethings causing it to fail I don't think that is it.

I shall try the carb cleaner technique. I forgot about this one. Although not sure why a vacuum leak would cause a complete start failure.

My injectors are getting voltage...although I am not fully sure how the signals interact with my ECU.

Hey that's a thought...ECU failure? I hear it's common to have a capacitor leakage on this car melting the board and causing shorts.

Also I noticed my cat sounds louder than usual....like obvious loud muffled humming. It does not get red like it is clogged and I have exhaust out the tailpipe...until this happened I never had this sound either

Oh also it happened the day after I brought it to pepboys since the were only ones open at the time to give me an oil change....used high mileage 75K+ oil.

If you removed and redid the wires than you may have switched them up inadvertently which can easily cause a no start problem. Redo the distributor, cap, and rotor, and make sure, then make sure again that you have the firing order correct and the cap, rotor and cap not reversed.

Way Fast Galant
06-15-2009, 12:55 AM
check for a vacuum leak get you a can of carb cleaner crank the car and spray the intake lines and see if the idle gets erratic



wow, that sounds so unsafe to me, and bad for the engine at the same time.


what did he mean by that lol

it meant, my car had an ignition problem that was diagnosed improperly and caused a lot of problems for me. and for the honda bit, that meant he wasnt a good mechanic to not notice the problem i had.

RedGalant2k1
06-15-2009, 09:00 AM
wow, that sounds so unsafe to me, and bad for the engine at the same time.


Nothing wrong with it...actually its a common diagnosis procedure. Carb Cleaner is basically just starting fluid, and will be burned up as soon as it is sprayed in. Plus sometimes it creates a nice puff of flames...lol

Galanttuner10
06-15-2009, 10:37 AM
Nothing wrong with it...actually its a common diagnosis procedure. Carb Cleaner is basically just starting fluid, and will be burned up as soon as it is sprayed in. Plus sometimes it creates a nice puff of flames...lol

haha the carb cleaner is fun to use and is quite helpful and the flames are cool just dont be right on top of where your spraying it

i hope you find something soon bro

bocochoco
06-16-2009, 04:36 PM
Well I cut a hole before my cat...I couldn't get the flange off so I was gonna cut the pipe and shove a crowbar thru the cat since I don't have emissions tests Pre-96 in Illinois. Then replace the pipe section

Still wouldn't start even with a decent sized hole....eliminating the cat as major issue....I eventually gave up and sprayed engine starting fluid into the intake....took 3 tries but it finally started...once it's warmed up it will start over and over but not cold....still dropping revs and choking when opening throttle.....does it neutral...drive...park...whatever....so not tranny

Still idles GREAT!!!! I can use my beloved mitsu as an alternative outdoor air conditioner!!!

I really don't think it's an issue with vacuum unless a valve is stuck....checked hoses....cleaned pvc....possibly bad EGR? Would that cause this?

I do believe if it's a 02 it would idle rough as stated before....

Maybe I really did get shit for gasoline at the hindi bollywood gas station....
I'm gonna go out later and get some iso-heat and some octane booster and jump the fuel pump for a few until it get's mixed well

....I'll be back lol

bocochoco
06-16-2009, 10:07 PM
The fuel treatment and octane boost offered no help....

I am at a loss again....

Is there a way to diagnose my ecu by myself?

skrap
06-17-2009, 09:07 AM
i honestly dont think its the ecu... did you pull your plugs yet??? clean them up??? also you can take out your fuel pump and check the screen sac on the bottom of it see it it is getting blocked. Could be the case since its only having issues when your sending more gas pressure. Also check to see if your tps is in spec. When mine first had issues it idled perfectly fine, then when i pressed the gas it was really bad almost like the feeling of bad gas.... check the tps first!!!!!!!

bocochoco
06-17-2009, 04:58 PM
My plugs are fine...Spark is a non-issue. Fuel delivery is excellent. Except I haven't had the chance to test injectors...

Anyone know voltage/resistance I should see off of them? Before on a autohold setting I would get like 5 1/2vdc to each wire I didn't check them all though

Also gonna do some research now on how to adjust my TP sensor....Kinda new to me

mko
06-17-2009, 06:02 PM
i think injectors get 12V constant power supply and the other pin gets the ECU control signal 0 and 12V pulses.

THe resistance of the injector is 12-14 Ohms

starh4x
06-17-2009, 06:32 PM
I thought I was misfiring to but then I realised If i quickly switched to Neutral the misfiring stopped. It stutters alot and it has no power. also slow to change gears. so does this mean I can be 100% sure its the trans? 5 speed swap time ?

bocochoco
06-17-2009, 09:24 PM
I thought I was misfiring to but then I realised If i quickly switched to Neutral the misfiring stopped. It stutters alot and it has no power. also slow to change gears. so does this mean I can be 100% sure its the trans? 5 speed swap time ?

I'd say if you have the money than do it.
Nothing better than a nice smooth new tranny