Honda D Series Forum banner
1 - 20 of 84 Posts

·
Registered
Joined
·
47 Posts
Discussion Starter · #1 ·
so it started off as a little thing when id be driving and all the sudden for like 1 sec the car would lose all power and check engine would flash but nothing to scan since it would go away happened like 3 times and then the car just wouldn't start one day looked at the coolant and it had some oil in it. changed the headgasket and pcv valve. It was driving fine and then after 90 miles the car started bucking(due to surging) and surging and check engine light came on for a IACV changed it the surging went away while its cold but as soon as it gets to operating temp it starts surging but the IACV code went away and now its a IAC malfunction code ive changed the throttle body gasket checked the tps with a mulitmeter and if the video was correct then my tps is good ive tried changing headgaskets thinking it was a bad one surging went away was test driving it felt low on power but i was happy the car wasn't surging, then it died and started surging again and IAC malfunction code came back. i sprayed carb cleaner on parts i could easily reach and no change in rpm and i dont think its a leak since it only surges while hot. if i start it cold no surging
people have told me distributor/ ignition coil or thermostat
forgot to mention when the car died after the second headgasket my scanner wouldnt connect to the ecu. the car wouldnt start either. then i pushed it home. left it to do some research and came back to no check engine light and the car started right up
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #2 ·
Update
Changed distributor and the car was fine for about 10 miles then the surging came back but only when the car was in motion. I would cruse in 2nd or 3rd and it’s still surging out it in neutral then while slowly coming out of the roll pull to the curb and stop as soon as I stopped the surging went away. Pulled Into my driveway hooked up my scanner to see live data and notice my tps is at 9.4% when not on the pedal is that normal? And while looking thru the data the car started surging like normal.
map is at 26 kpa on surging.
surging is about 1.4k-1.6k
 

·
BATSLOMAN GIVES NO FUCKS.
Joined
·
5,707 Posts
did you bleed the coolant system?
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #5 ·
Update
I closed the idle screw all the way and the surging as stopped

Also, could you have accidentally swapped the IAC and IAT plugs when reconnecting?
Just checked, I didn’t. each plug is different

did you bleed the coolant system?
I think it’s bleed I left it running till fans are on and no bubbles
 

·
Registered
93 Civic HB SI, 95 Civic HB CX
Joined
·
2,237 Posts
If you've shut the bleed air screw, and the car still runs pretty normally, you likely have a vacuum leak from somewhere.

To verify, keep the bleed air screw shut, now take the air pipe off the throttle body and stick your thumb in the IAC air flow hole to completely cover and plug it.

If the car still stays running, you have an air leak large enough on the other side of the throttle body, to where the engine doesn't even need IAC or bleed air at all to stay running. Find the leak.
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #11 ·
If you've shut the bleed air screw, and the car still runs pretty normally, you likely have a vacuum leak from somewhere.

To verify, keep the bleed air screw shut, now take the air pipe off the throttle body and stick your thumb in the IAC air flow hole to completely cover and plug it.

If the car still stays running, you have an air leak large enough on the other side of the throttle body, to where the engine doesn't even need IAC or bleed air at all to stay running. Find the leak.
so I kept the idle screw closed all the way and covered the IACV port and it did die but after like 2-4 seconds idk if thats normal. and as a side note I did this while the car was cold, would that matter since the surging only happens when its hot.
would it be bad just to run the car with the idle screw closed all the way
also the gasket i got for the store was like a gasket both for y8 and y7 but the hole for the coolant didn't have that like copper washer and it was like a metallic material like for an exhaust so i ordered a new one from Honda figured id just go back to OEM.
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #12 ·
Update. Drive 10 miles with the idle screw closed all the way. And then the CEL(p0505) came on at a red light but no surging. As soon as I stepped on the gas the car would surge till I was able to give it more gas. So the only time it would surge is when I gave it a little gas and it was almost like riding a bull with all the bucking the car was doing.
 

·
Registered
93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
Joined
·
1,260 Posts
Tps reading 9.4%? What kinda shape is your alternator in? Any ac voltage bleeding into the system? Charging higher than 14.7 volts?
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #14 ·
Tps reading 9.4%? What kinda shape is your alternator in? Any ac voltage bleeding into the system? Charging higher than 14.7 volts?
How would I check that. Ya on my live data on my scanner it’s reading at 9.4%

Update
I decided to try to bleed the coolant again and I found that the bottom screw In the middle for the intake manifold was completely loose so I tightened that up and started bleeding coolant the coolant had lots of little micro bubbles that just wouldn’t stop coming up. Lasted about 6 mins of micro bubbles. Then I had to call it quits since my neighbor asked me to haha it was only 8:30 tho. The bubbles had some breaks where there where none but it would always come back

Update
I decided to try to bleed the coolant again and I found that the bottom screw In the middle for the intake manifold was completely loose so I tightened that up and started bleeding coolant the coolant had lots of little micro bubbles that just wouldn’t stop coming up. Lasted about 6 mins of micro bubbles. Then I had to call it quits since my neighbor asked me to haha it was only 8:30 tho. The bubbles had some breaks where there where none but it would always come back
Liquid Water Blue Fluid Paint
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #15 ·
update I’ve changed the IM gasket. And map sensor. Seems to have made the surging Less violent. The IM gasket helped a lot. I did mess with the idle screw so I read somewhere to close it all the way and then back it out 2 turns did that but surging is still here and only when cold. Car still throws CEL P0505. When I erase it the car is more smooth but when the CEL comes on the car bucks a lot more. Please I need HELP. I’ve honestly done everything I can think of and have no idea what to do now
 

·
Registered
93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
Joined
·
1,260 Posts
Set your volt meter for ac voltage, ground the com lead to battery- and touch the red one to alternator output, if no ac current check the charge voltage off idle where it surges, very occasionally I see charging system issues cause surging from bad sensor readings. I would also replace the pcv valve to eliminate that as a possible issue, and pull the battery cables for 15 mins to clear the ecu and relearn idle.
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #17 ·
What cable is the alternator output? I changed the pcv already sorry forgot to mention. And I will pull cables rn. Or should i do it after checking alt. Also do I do this alt method With the car on?

Set your volt meter for ac voltage, ground the com lead to battery- and touch the red one to alternator output, if no ac current check the charge voltage off idle where it surges, very occasionally I see charging system issues cause surging from bad sensor readings. I would also replace the pcv valve to eliminate that as a possible issue, and pull the battery cables for 15 mins to clear the ecu and relearn idle.
Sorry forgot to hit reply so idk if you would be notified if I reply so I’m sending another one.
What cable is the alternator output? I changed the pcv already sorry forgot to mention. And I will pull cables rn. Or should i do it after checking alt. Also do I do this alt method With the car on?

Set your volt meter for ac voltage, ground the com lead to battery- and touch the red one to alternator output, if no ac current check the charge voltage off idle where it surges, very occasionally I see charging system issues cause surging from bad sensor readings. I would also replace the pcv valve to eliminate that as a possible issue, and pull the battery cables for 15 mins to clear the ecu and relearn idle.
Also so I’m looking for the multimeter so say 0 right I don’t want any ac current.

Also forgot to mention since I didn’t think this would be a problem but there is a huge crack on the manifold next to the o2 sensor on the top of exhaust manifold
 

·
Registered
93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
Joined
·
1,260 Posts
Alt output can be tested at the fusebox where the alt cable connects for easy access, any ac current above 0.4v I find usually can cause sensor reading issues test with engine running and in the range it normally surges while fully warm.
Since you are saying there is fuel smell when it surges the crack next to the o2 sensor might be exacerbating some other issue and contributing to the surge.
My suggestion would be as follows: test alt replace/repair as needed, resolve tps reading 9.4% while idling, if its still surging after that start pulling and capping every vacuum line one at a time until you find the one that makes the surge stop, then investigate that system thoroughly.
 

·
Registered
Joined
·
47 Posts
Discussion Starter · #19 ·
Alt output can be tested at the fusebox where the alt cable connects for easy access, any ac current above 0.4v I find usually can cause sensor reading issues test with engine running and in the range it normally surges while fully warm.
Since you are saying there is fuel smell when it surges the crack next to the o2 sensor might be exacerbating some other issue and contributing to the surge.
My suggestion would be as follows: test alt replace/repair as needed, resolve tps reading 9.4% while idling, if its still surging after that start pulling and capping every vacuum line one at a time until you find the one that makes the surge stop, then investigate that system thoroughly.
how would i go about the tps sensor and what does the 9.4% mean. i got the 9.4% from my scanners live data. does it mean like 9.4% open? and i will try to do all that tomorrow hopefully it works. thanks for your help i appreciate it

Alt output can be tested at the fusebox where the alt cable connects for easy access, any ac current above 0.4v I find usually can cause sensor reading issues test with engine running and in the range it normally surges while fully warm.
Since you are saying there is fuel smell when it surges the crack next to the o2 sensor might be exacerbating some other issue and contributing to the surge.
My suggestion would be as follows: test alt replace/repair as needed, resolve tps reading 9.4% while idling, if its still surging after that start pulling and capping every vacuum line one at a time until you find the one that makes the surge stop, then investigate that system thoroughly.
i was looking around for the idle % and supposedly for civics its normal for 9-9.9% at idle but i will check it with a multimeter tomorrow. need like.4 closed and 4.9 open right?
 

·
Registered
93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
Joined
·
1,260 Posts
i was looking around for the idle % and supposedly for civics its normal for 9-9.9% at idle but i will check it with a multimeter tomorrow. need like.4 closed and 4.9 open right?
Depends on the scanner you are using, mine generally reads them a tiny bit high, like 4-5.5% but looking at voltage instead of % it shows correct, the important thing is it not fluctuate too much between engine off and engine on.
 
1 - 20 of 84 Posts
Top