SR20det boggs at once it hits boost mimit

[sr240noob]

After 4 months of swapping out engines and Fixxing the bugs i finally got to drive it but ran into another issue. I drive, once it hits boost it starts to bog and pop. It idles perfect and when im driving it easy, it acts normal. But once i give it gas it runs like ass. Maybe like its dumping to much fuel or not able to burn off the fuel its getting properly. Any suggestions?

im running stock boost on the stock ecu. its all just about stock but i have a fmic and the filter is ran down next to the FMIC. Any ideas?

[HAWAII]

maybe it is not getting enough gas? You changed the fuel pump

[Artigo]

Do you hear the fuel pump turn on when the car gets power? This sounds similar to the problem I had. Check the pump and boost leaks.

[sr240noob]

some reason i was thinkin to get a fuel pump too. i still have the stock ka pump. It seems to reach boost well. but opnce it gets up there it will bogg. definately sounds like it may be a fuel issue. So i will try a pump and see how that helps. Cus at idle and revving up in neutral it runs perfect. its just as i am driving and under boost.

[aNskY]

boost leak

[sr240noob]

i guess re-tighten all the intercooler pipes? it gets to 7ps1 real well and seems to be boosting fine. Which i guess a boost leak makes sense. ill try rodoing the pipes and see if that helps. Thank you.

[S14_Kouki]

Yo fuckin change your fuel pump NOW, stock sr's r 370cc prob almost 100cc bigger then KA injectors

[lilrusty]

^^^^ agree!!! you should have done your fuel pump before you even tried to turn on your car. ESPECIALLY that you did an sr20 swap. but i think u have a boost leak somewhere

[sr240noob]

LOL, Ok Fuel pump ordered. also ordered a boost leak tester. hopefully after this i will be able to full throttle it! Thank you all.

[aNskY]

While you definately need more fuel pressure than your ka with an SR, running a stock fuel pump will not cause the symptoms you are describing. Have you inspected your plugs?

you could have made a boost leak tester for like $1 -- let us know how it turns out

[steve shadows]

After 4 months of swapping out engines and Fixxing the bugs i finally got to drive it but ran into another issue. I drive, once it hits boost it starts to bog and pop. It idles perfect and when im driving it easy, it acts normal. But once i give it gas it runs like ass. Maybe like its dumping to much fuel or not able to burn off the fuel its getting properly. Any suggestions?

im running stock boost on the stock ecu. its all just about stock but i have a fmic and the filter is ran down next to the FMIC. Any ideas?

This is your ignition FOR SURE.

I would check your ignition grounds. If you trace the Ignitor Coil Wiring harness in the back near the timing Loop (that you use to check your timing with a timing light) you will find a ground wire that goes to the back of the head and is bolted there. If this starts to come loose or is not hooked up you will have a progressively worsening mis-fire.

I know because it happened to my last race car.

Also check your plug gap and make sure (NGK heat range 6,7 or 8) at least for cold range and also make sure you Plug gap is .028 or smaller.

Cheers

[sr240noob]

This is your ignition FOR SURE.

I would check your ignition grounds. If you trace the Ignitor Coil Wiring harness in the back near the timing Loop (that you use to check your timing with a timing light) you will find a ground wire that goes to the back of the head and is bolted there. If this starts to come loose or is not hooked up you will have a progressively worsening mis-fire.

I know because it happened to my last race car.

Also check your plug gap and make sure (NGK heat range 6,7 or 8) at least for cold range and also make sure you Plug gap is .028 or smaller.

Cheers
Ill check that as soon as i get home. I was listening last night and it seems at idle there is a very small misfire every few soconds as well. Had me thikin plugs. So i will grab some new plugs tonight and try that as well as grounds. Is the ground your talkin about the one on the rear passenger side of the head?

[steve shadows]

yes, but you will know it, it's the only wire coming off the coil pack harness that bolts to somewhere.

[sr240noob]

it seems to be grounded well. it seems nice and tight. Also my plugs look fine too. Any other ideas?

[aNskY]

check your chassis ground too, my old car rusted right where the chassis was grounded, but it caused a constant misfire, along with intermittant lack of power altogether..

[sr240noob]

ok will check it out. Ill look over all my grounds and see if that helps. I checked all the engine grounds and it didnt help much. I put all new OEM coil packs on it and plugs as well. I dont get a Check Engine Light to turn on so its gotta be something minor i just can figure out what it is. Maybe ill install that fuel pump and check for boost leaks and see if that helps. Although it does seem like an ignition issue.

[vladimir240]

man, im having identical issues, the shitty boost and occassianal missfire at idle. and everything else is fine. lame. it all started after i turned the boost down with a manuel boost controller, and been like the sense. def post what you find out.

[aNskY]

have you inspected the plugs yet? they could tell you a lot...

[vladimir240]

please explain, i had to change one of them. what should be looked for?

[aNskY]

wetness / fuel smell (rich condition), white electrode (detonation), chippage (detonation),

basically if theyre not all just a slight lightish brown color (assuming youre running pump gas) on the tip something is wrong, and you can trace the problem back to that cylinder... when you say you had to replace ONE .. what was wrong with it? also what plus are ya using? may be too hot or gapped too wide...

[sr240noob]

yea i checked my plugs and they were a light brownish color but they seemed pretty wet. almost like they were fireing but not enough. Cus they were pretty wet. i went over all the wireing and it seems fint too. the harness was all soldered and done correctly. Also i noticed when i unhooked my Apexi AVC-r it idled a little better. but still bogs. im gonna see about shooting a video of it today and see if it makes things more easy.

[DataXUnknown]

Maybe clean the injectors out? Z32 Fuel Filter? and are you sure you got your vacuum lines running to the right places?

[vladimir240]

hmmm, well when i had to change one out it was cause i had a bad injector and and coil pack wire was messed up, so that plug had lots of black on it(2nd cylinder). since then i have replaces all the plugs too. im using the NGK's for 91 sentra se-r, store gap...

[s14_mike]

check to see if your air flow meter is plugged in.

[vladimir240]

if you're talking about the MAF, its good.

[sr240noob]

So Between fixxing boost leaks,New plugs, regrounding all grounds, and a new fuel filter it seems to be doing much better. I still get an ocassional backfire but i prob just need to install my new fuel pump. Thank you all so much for your help. It saved me alot of time and money. Again Thank you all. I will post update after in install
fuel pump.