SR20DET bogging on boost

[silviaz]

Hi guys, I've a tiny problem after my swap. I was thinking my problem was bad gas but now i'm about 30 liter of 91 octane and 20 liter of 87 octane + octane booster added and I can feel my engine bogging when the boost start at 3000rpm so I have no power at all. I'm 100% sure it's boosting because I hear the bov and the turbo spooling even at low rpm.

There's no black smoke, MAF is good - checked every coupler of my sidemount intercooler, cold pipe and hot pipe, no boost leak.

Vaccum hose are brand new - Idle is great, 800rpm

New spark plug, new 300zx fuel filter, new walbro fuel pump, new turbo gasket

I'm about 80% sure it's missfiring because there's enough gas to the engine, so i'm thinking about coilpack. They are probably 15 years old!

I've also noticed today when I was on the highway, at 2000,2500,3000rpm, even whitout boost it was bogging a bit, like if there was not enough gas. So it's probably due to the miss fire.

What do u think ? I'm trying new coilpack this sunday, but how can I verify easily which one is bad ?

If it was the ignitor chip, I suppose my miss firing had to be worst.

[Om1kron]

how are your turbo gaskets? you don't smell gasoline? i get the same thing but i know i have a boost leak.

[silviaz]

how are your turbo gaskets? you don't smell gasoline? i get the same thing but i know i have a boost leak.

They are brand new, Changed 3 gaskets. It Doesn't smell gas or anything else. On neutral, I can rev the engine without noticing it's misfiring, it's only happening under load, except when I was riding hope last night and I found my car bogging when I was pushing the gas.

[silviaz]

I removed my coilpack... it was full of humidity in 3 cylinder..... with moisture...... I know why...... my friend decided to wash my engine...... I told him to not to shoot water there but ohhh well.....


I'll try the car today...... hope my coilpack aren't dead because of that.

[LoanShark]

I have the exact issue. Same 2.5-3k breaking up. From a dead stop through every gear it does it too. But, I found every now and again it'll let me get it up to about 3.5-4k before it starts that BS. Boosts stock also, sometimes creeps to 8-9.

The greddy informeter also reads 25-28 ignition cruising at 3000rpm. it reads about 14 ignition when breaking up.

I thought it was the Bee*R at first but, I have it in the off position.

I'll take the plugs out later and maybe check the coils but, pretty sure they're okay.

good luck

EDIT: ran into a shit storm last night on my way home from a drift day. Worst one I've been in. Got off an exit and the lane i was in got FLASH FLOODED. Bogged out and finally died. Pushed it 30 yards to the gas station, took the maf off, dumped water out, bathroom hand dryer worked, took the shitty filter off, used a cotton glove til I got a proper filter when the store opens.

point is, The issue at hand was happening even before the flood.

[silviaz]

Problem solved. It was due to the humidity between my coilpack and my sparkplug....... now it's running fucking great and boost like mad.

sr20det are awesome engine.

Loan, check if your coilpack are good. I'm pretty sure it's your problem., you should try another set from a friend. you have nothing to loose, except time.

[KoukiMonsta]

FYI to check coil packs u can idle motor and disconnect them one at a time, if u disconect it and engine starts acting up its good. disconnect and get NO change= no spark

[LoanShark]

yeah, mine idles and revs fine. Its shitty under load.

[fliprayzin240sx]

Check your sparkplugs Shark...make sure its gapped properly down to .030-.028

[KoukiMonsta]

yeah, mine idles and revs fine. Its shitty under load.

boost leaks to, i had same issue and realized one of my hose clamps at intercooler came off.

[LoanShark]

eyeballed the plugs, coloration was normal. Havent checked gap yet. Pretty sure its right, it was rebuilt/put back together by Forcedfab. They do lots of SR.

Kouki monsta, i hope its as simple as a boost leak. Thanks guys

[KoukiMonsta]

well defanitly gap them, and ya i hope its an easy fox for u

[LoanShark]

My update-

Idle vac: 19-20
Start up and idle timing: 15

Unplugged maf: idle stumbled, rough rev, white smoke

Loaded ignt: 20-27

Loaded 3000rpm studder: timing dropped progressively lower and bottomed out at 14

Came back and free revved: revved once to 6000 before getting the stumble. Progressively stumbling lower and lower RPMs. Timing read a steady 36 idling.

It reached a point where it wouldnt boost. Vac would reach 0 and stumble there.

With car idling, we unplugged the injector clips one at a time: idle stumbles each time.

Did the coilpacks one at a time:

#1 is arcing or sparking or shorting. Rapid electrical clicks like a stun gun. Blue sparks. Idle didn't change. When we took it all the way out, there was a moisture to them on one side. Let that one dry out and went at it again. No Joy.

#2, 3, 4: idle stumbles, no arcing or sparks

Switched #1 coilpack and #2: #1 was now normal. #2 was sparking. Its a Bad coil.

White smoke each time. Does the timing sound right?

I'll still do a boost leak check next time and check the plug gap.

Thanks for all the help/advise.