Honda eb3500 rpm surge hunting - Honda 6370C - Parallel Power Kit For EU3000i

The typical cause for "governor hunt" is a fouled carburetor. Could also be water in fuel.

Suggest you drain fuel, especially the carburetor fuel bowl, and put in fresh fuel. A fuel system additive such as Sea Foam will likelyl clear minor carburetor fouling.

Measure and add fuel additive per instruction... too much additive will cause high specific gravity and improper air/fuel mixture (poor running or no run).

scan it yet, a FULL OBD2 scan? why not?if not.
now is the time...


the 1.8L J18 engine, same as the older Sidekick sports used.
same engine , know it I do.
its the precursor to the J20, (j18 is under-stroked, j20 with many of the same parts. inside)
the back fire means explosion sound to rear end of tail pipe?
yes, that is rich raw fuel in the muffler. plus Air.
if there are exhaust cracks and then engine goes rich this can happen( a double failure)
if how ever BACK means, back to the Air cleaner, then that be different reasons, (timing)


engine now starts.?>
engine runs.? has full power, car drives ok.?
JUST?
SURGE,. you never said.

does engine get hot? 180F or more and holds (y/n)
ever get a full tuneup this decade,
most dont so i tell you, bad spark causes, misfire and raw fuel is wasted to the exhaust and sure can go boom.

surging usually means the ISC can not control idle
so it hunts, (a suzuki software engine on all 90s engines)
PCM errors, inside it. (dangerous too)
a modern car, if idle goes too high the ecu commands the ISC closed
and holds it there solid, (safe way , no hunting allowed now)]
so if this car surges, it's , lean engine.

some think flooding is surging.
and this is usually below 800 rpm,
almost stalls, then corrects, seems like a surge.

next time post rpm range of surge.?????

do not drive a surging engine, do not be like Toyota drivers. (over 800 rpm hot)

surge from 400 -800 rpm is class 1 surge.
surge from 800 to say 2000 RPM is class2, and very dangerous to some folks, (key off, get car fixed, tow it)

The ECU controls idle speeds. (hard coded servo controls)

well gee, there are 50 reasons.
did you scan the PCM yet, if not ,why not?
when the idle surges, that means.
NO RPM ranges stated, if super low rpm check EGR.

1: engine lean and ISC dead, or cant handle the huge engine power drop..The PCM can even make this worse!, buy hunting the ISC to find spec, idle and failing... to...
2: or any of 50 other things causing huge engine power drop and PCM can't maintain idle controls.
super lean burn.(bogging)
super rich burn, misfire for 50 reasons.

i cant hear your engine,nor feel it, or see it shake from gross misfiring.
no can i drive it and see/feel power loss,
can I?
asking net bunny's this (blind as bats)
is "OVER THE TOP" no?
so here , ill toss the dice for you
and guess gross misfiring.
ever get a tuneup this decade, if not bingo , no?

and the others...

http://jeepdied.com/Misfire101.html

link even has the 50 cause list, to show the futility of guessing!
we do 1 to 10 tests. and find it.
for sure.

as you can see EFI systems are complex.
gue$$ is not only expensive but can net you 2 problems easy.

This engine behaviour is called hunting. There are many articles on line as to causes, below are links to the first that I found when doing a BINGsearch for the word HUNTING.
Good Luck



http://dmctalk.org/archive/index.php/t-603.html

http://www.autoserviceprofessional.com/article/92420/the-dreaded-engine-surge

hunting or surging ilde. name the 2 RPMS, low and high , is it hot or cold engine this issue.? 400rpm or 1000 or 2000 all are diff.causes.
no year, stated. so cant help.
but ill answer in the generic,
1: the ECU (got a carb,? )
the ecu controls idle speed at all times.
if not , there is a problem (you)
A: air leaks in the induction will make motor race at some point the ECU/ISC loses control. and hunts. trying hard to correct it.
b: egr stuck open idle too low, iSC cant correct it,, bad EGR.
c: engine EFI running way too leak starving for fuel so it hunts for 2 reasons < ISC hunting, and lean does that.
lean is gross power loss and opening throttle bogs the engine.
so is double bad. ISC makes it worse,

all this breaks down to 2 reasons.
1: ISC bad. in some way (gummed up. or restricted inside)
2: bad fueling or air leaks. vacuum leaks.

try answers , the hot cold question and the 2 speeds, of the hunt.
lowest rpm and highest of the hunted range of RPM.

Surging or hunting as it is know is due to a fuel blockage in the carb, if the main jet is part blocked you need to clean it, remove the float bowl and blow out the jets with compressed air.

clean the MAF sensor with carb cleaner if you have one in the big air intake hose. Small heated wires inside. Causes lean mixture

is gas old? is choke on? is fuel turned on?

Hi.it sound a lot like a ignition coil coils tend to do that if its got a crack it Swell when the temperature rises

no the surge that high is not normal a normal cold start should go to around 1500 then settle slowly to 750 or so but this all depends on engine temp and ambient air temperature