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Throttle cuts at full boost load

1588 Views 36 Replies 8 Participants Last post by  robgoof
Weird one here boys. I have a d16y8 on a edel. Turbo ecu and a simple eBay turbo kit on 7lbs. Car runs fine and builds boost but when I’m at WOT and hitting full boost the car decides to fall up on its face and just stays at 4500 to 5000 rpm and starts backfiring and popping. Any ideas on how to fix this? Car is not in limp mode either
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It doesn't sound like he's got a wideband.... hoping for plug and play turbo with no boom
yeah probs..

plug and play should be left to vibrators and nintendo..
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You have a “dumb” ECU that can only respond to discreet inputs (MAP) so I seriously doubt it’s the issue. I would double check the hot side for manifold/turbo housing cracks and the cold side for boost leaks/vacuum leaks. I would check the compression and timing as well. I hope you at least have a boost gauge, what does it read at WOT?
You have a “dumb” ECU that can only respond to discreet inputs (MAP) so I seriously doubt it’s the issue. I would double check the hot side for manifold/turbo housing cracks and the cold side for boost leaks/vacuum leaks. I would check the compression and timing as well. I hope you at least have a boost gauge, what does it read at WOT?
The only reading I can get outta the boost gauge is right under 5-6 pounds and then the car just gets stuck at 4500 rpm and almost sounds like an anti lag that just doesn't stop. After I get off the gas you can hear everything escape through the BOV
It doesn't sound like he's got a wideband.... hoping for plug and play turbo with no boom
Gonna get a wide band on there ASAP just tryna find another turbo down pipe that has a bung welded on. However the car seems to be running rich. Which I assumed when I was changing the gaps on my plugs.
Are you on a STOCK honda MAP sensor?

It is only good to around 10psi.

Very possible it is going bad. Watch MAP sensor votlage if you have a way. Does the edelbrock ecu piggyback offer ANY sort of controller or output screen?

I honestly did not know edelbrock even HAD a piggyback.

DOUBLE CHECK for its existance
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Are you on a STOCK honda MAP sensor?

It is only good to around 10psi.

Very possible it is going bad. Watch MAP sensor votlage if you have a way. Does the edelbrock ecu piggyback offer ANY sort of controller or output screen?

I honestly did not know edelbrock even HAD a piggyback.

DOUBLE CHECK for its existance
No the ecu doesn't have any sort of controller output and I believe I'm on a 3bar MAP sensor. I tried a Hondata 4bar MAP sensor and the car didn't even want to idle, the car shut off immediately.
There's your problem. Put your stock MAP back on. You didn't list this in your "full build list", this would be part of the "leave no detail out" request.

You have zero tuning provisions to scale for a new MAP sensor, so your ECU is freaking out.

This plug and play edelbrock kit you're using is only designed to work on a completely stock engine and electronics setup. You are boost limited to what your stock MAP can read in this case, about 10PSI.

You cannot install a new MAP sensor without having the ability to tune. The edelbrock box is not a tuning solution.
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Was there a vacuum hose attached to that nipple near the electrical plug?

ANd yes, piggyback means stock MAP sensor. No if's and's or but's


If there was no hose to that nipple, the edelbrock unit does NOT see boost and does NOT know to add fuel and pull timing.
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I would highly recommend emailing edelbrock, and asking for the manual in PDF format for that unit.

You will need to know any and all identifying information the casing provides, as this is quite old.

You may have to use the wayback machine website to find 10+ year old information on it.
4bar eh
gotta pry it out of him sheesh.
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Was there a vacuum hose attached to that nipple near the electrical plug?

ANd yes, piggyback means stock MAP sensor. No if's and's or but's


If there was no hose to that nipple, the edelbrock unit does NOT see boost and does NOT know to add fuel and pull timing.
No, we thought the 4 bar would make a difference we switched it back to the stock one after we didnt get it to start or even cruise. Also there was a hose connected to that vacuum line.
I would highly recommend emailing edelbrock, and asking for the manual in PDF format for that unit.

You will need to know any and all identifying information the casing provides, as this is quite old.

You may have to use the wayback machine website to find 10+ year old information on it.
After I put the stock map sensor back on the car ran perfectly fine and even trying to roll into it, the car still did the same thing got to 4-5k and just fell on its face. I had done pretty much all I could think of including re-locating my o2 sensor, doing a new IAT sensor, retarded timing 1° for every 1 psi of boost I was running and re-gapped my spark plugs. Nothing changed in the way the car was performing. Beginning to think the actual edelbrock ecu is junk since it is really old. Thinking of switching to a p28 w/ s300 to get more in depth details about the car and better tuning abilities. Need to get a AEM AFR ASAP though.
That nipple on the edelbrock NEEDS access to boost pressure. T off the fuel pressure regulator circuit.

why would you think changing the MAP sensor without being able to tell the ecu differently, would work?

Programming is super simply. The software reacts exactly as it is told. If you cannot change the programming, then keep the stock stuff.

re-locating O2 sensor does not do anything, It just needs to be on the downpipe PAST the turbo, and ensure there are zero exhaust leaks.

retarding timing per 1 pound of boost? how? If you moved the distributor, MOVE IT BACK to base timing.


Again, the edelbrock, when hooked up properly, should help.



At this point, I highly recommend going to stock intake and exhaust, and running stock until you have ALL the information you need to go forward. This is going to kill your engine.
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I've read everything and coming in with my 2c on this. Few things I'd like to know, 1: since you've gotten the car from the previous owner, has it ever ran properly? Did the issue just show up while you owned it? 2. If it did develop since you've owned it, what led up to it? Did it just start out of the blue or did it slowly creep in? 3. Does it happen in a particular gear? Or rpm (not boosting), or just at WOT Boosting? I'm asking because I had a friend with a similar (if not the same problem) even when he was N/A and it took the muppet a year to figure it out because his a bit stubborn at times.
retarded timing 1° for every 1 psi of boost
You cant physically do that without a better tuning solution. Distributor on a stick through the firewall?
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You cant physically do that without a better tuning solution. Distributor on a stick through the firewall?
needs pwm shock to the butt so you know when to go full retard.
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