Honda Help! shitty idle , now stalls.

NYSpeed Automotive
1

Need some help with the idle with my 98 gsr. First and main thing being the bouncy loopy idle. The car idles from about 700 and then bounces down and hits rock bottom and almost stalls once the car is fully warmed up. Today it actually did stall and continues to do so after i put in new plugs and wires. ( the old ones were shitty as hell and were shot)

It had an fmu in it that i pulled out.
I took out the iacv and cleaned it and put it back in.
Just put a fresh set of plugs and wires in it.
check over a few vacume leaks and couldnt find anything.

any insights on what it could be?

After the new plugs, cleaning the iacv and taking out the fmu , it actually runs shittier and stalls out now at idle.

What else could it be?? the car doesnt have an o2 sensor , but ive never really heard of a car staling out and having a loopy idle because of it.

2

any cel’s?

3

coolant, bleed the cooling system, thats known to cause bouncy idles.
Also check your grounds.

the stalling could also be a fuel issue.

4

if there’s no check engine, it sounds like a vac leak you just haven’t found yet.

stock ecu yes?

5

take needle nose pliers and squeeze every vac line when the car is running…if you hear a change in the idle when you squeeze a line, that one has a leak

6

yea one for the o2, misfires and the map sensor.

just got new plugs and wires today, and replaced the map, still shitty even worse now

yes stock ecu i bet its a vacume leak i just suck with them

ill have to try that

7

EGR causes a rough idle and can even lead to stalling. Quite often it is the vac lines like has been mentioned before.

8

hmm yea ill have to go over each vacume more closely.

9

spray bottle + soapy water = ftw

10

you can also mist WD-40 over vacuum lines and that will give you an audible change in the idle as well…

also note…that CLEANING the iacv may not do anything if its no good anyway…as a last option replace that

11

hmm i was thinking that too.

ive tried wd40 before when i had vac leaks in my old teg n it didnt work

12

I’d get a fuel pressure gauge on it. Could be a clogged filter.

13

i got a spare iacv if you want to try it,i bet its that manifold

14

doubtful

15

I wouldn’t want to be so certain about something that is so simple to check. My Trans Am did the same thing and it turned out to be fuel filter/fuel pump related. I spent tons of time fucking with everything else like IAC, MAF, plugs, wires ect ect like the original poster. If I would’ve just put a gauge on the rail I would’ve saved myself tons of time. It’s just the point of taking a minute of time to rule something completely out.

16

you advice is helpful,but to the wrong crowd.
shitty honda idle is about 95% iacv/vac line related

17

tru that , def try the IACV , i had that same problem … sucked

18

didnt mean to sound like a dick…the filters never clog on eg’s and tegs

19

tru my fbod was fuel filter related and it had the same symptoms. like said, if the iacv isnt the problem …maybe just try it. i know my dizzy cap was like loose or something and it wasnt sparking and the cylinders werent firing or some shit and the idle would drop.

i have no idea if that is even relevant or true, just some dumb input

20

Then I guess they shouldn’t even have fuel filters, because Hondas only have clean gas in their stainless steel tanks. Any good tech always checks FUEL & IGNITION.

Also WD-40 is far from highly flammable, propane or carb cleaner finds vacuum leaks easier with less mess