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Discussion Starter #1
hey everyone, so basically a couple days ago i got my car tuned on 23psi. car was running nice until i noticed it wouldnt boost past 13 anymore.

- what ive done so far is replace my boost controller, i have a new AEM boost solenoid now.

- checked voltage to controller, full 12v are being received.

- checked for any leaks in both hoses and clamps all around, nothing.

ill link the datalog file aswell as a screenshot for people to check out, i dont have enough experience with hondata to know what im looking at. the MAP sensor never goes higher than 12-13 i believe. it's a 3rd to 5th gear pull.

Also worth mentioning, my O2 sensor just went bad but i dont think that would impact any of this would it?

https://mega.nz/#!ioVm0Cxa!snThzy1Zq4TGoLhdcpKu8Il8ewnqJkqYgO4DI_BoLE0
 

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Does the car still feel how it was right after the tune?

10psi is a big difference.

If the car doesnt feel any different, that 23psi might be an oddball reading that combines atmosphere.


If car feels quite different, make and use a boost leak tester.

homedepot, rubber pipe caps and clamps.

Use hairspray as a lube and glue on couplers. When wet, lubes nicely, when dry, glues the shit in palce pretty well.

Could buy a tire valve stem, and pump the tester to around 30psi and see if it can hold it fairly steady for several minutes. idle screw and throttlestop will leak a little air, so it is normal to see a minor drop.

Then spray with soapy water to find leaks if they exist.

If nothing is found, pull the wastegate actuator off and see if there is any damage to gaskets or the valve itself.
 

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Discussion Starter #3
Does the car still feel how it was right after the tune?

10psi is a big difference.

If the car doesnt feel any different, that 23psi might be an oddball reading that combines atmosphere.


If car feels quite different, make and use a boost leak tester.

homedepot, rubber pipe caps and clamps.

Use hairspray as a lube and glue on couplers. When wet, lubes nicely, when dry, glues the shit in palce pretty well.

Could buy a tire valve stem, and pump the tester to around 30psi and see if it can hold it fairly steady for several minutes. idle screw and throttlestop will leak a little air, so it is normal to see a minor drop.

Then spray with soapy water to find leaks if they exist.

If nothing is found, pull the wastegate actuator off and see if there is any damage to gaskets or the valve itself.

it feels a bit different, 3rd gear is by far the most noticeable.. it just feels like the car's making half of what its supposed to. ive already checked my external wastegate! Ive tried cleaning it out as much as possible with a bit of brake cleaner for the carbon build up and still nothing. The only thing i can think of is maybe a poor connection somewhere? or maybe a leak in the vaccum hose leading to the gauge? even though it got full voltage, my car sometimes bogs out when someone touched the jumper harness for my obd1 ecu, but it hasnt done it in a couple days.
 

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many jumper harness's around are known to be a common cause for random or intermittent issues.

while I doubt it would cause a major boost difference, perhaps the MAP sensor signal is getting messed with, and your tuner implemented some sort of boost cut when things are reading badly.


Have a buddy shake or move the jumper harness while you are idling. Dont wanna be driving in case it makes a possible issue worse.


Generally, crappy jumper harnesses are simply bad crimps, or shielding is not correctly grounded, or not present on the encessary wires.


For sure you want shielding on distributor housed sensors (position sensors) and perhaps MAP and TPS signal wires.


Might be worth a check.
 

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Looking at the datalog you posted in the bottom window where you have RPM, VSS, TPS and MAP, unless there is some weird scaling issue going on where the values for MAP are just tiny in comparison with RPM for example, I don't see the MAP moving off of the bottom of the graph hardly at all.

I don't think it's scale, because all of the other components in that graph window seem to scale independently of the other component scales. "Shooting from the hip recommendation" looking at that screenshot, I think you have something up with the MAP sensor/wiring/etc.

Do you have a wideband AFR gauge installed? Are you [lean/rich/on the money] during times when boost is present? You want to make sure you are NOT boosting while you have problems with MAP, #saveyourengine lol.
 

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Discussion Starter #6
Looking at the datalog you posted in the bottom window where you have RPM, VSS, TPS and MAP, unless there is some weird scaling issue going on where the values for MAP are just tiny in comparison with RPM for example, I don't see the MAP moving off of the bottom of the graph hardly at all.

I don't think it's scale, because all of the other components in that graph window seem to scale independently of the other component scales. "Shooting from the hip recommendation" looking at that screenshot, I think you have something up with the MAP sensor/wiring/etc.

Do you have a wideband AFR gauge installed? Are you [lean/rich/on the money] during times when boost is present? You want to make sure you are NOT boosting while you have problems with MAP, #saveyourengine lol.
when im boosting the leanest ill go is maybe 12:1, i called my tuner yesterday and he thinks there's a short somewhere with the boost controller which is causing it to stay open all the time rather than pulsating. im gonna replace the jumper harness regardless and see if that fixes the issue. if not then i guess its my harness :(
 

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Discussion Starter #7
also, might be worth mentioning, when i put my car into accessory mode and the fuel pump primes, i can also hear a loud click from the solenoid. Is that normal? ive never really noticed it doing that in the past before..
 

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Have you tried running the turbo off the wastegate and NOT the boost solenoid?

Try that and do a few datalogs and see if it stays within good AFR's.


Any tuner working with a boost controller/solenoid will do a baseline off the wastegate to see where the starting point is.
 

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Discussion Starter #9
Have you tried running the turbo off the wastegate and NOT the boost solenoid?

Try that and do a few datalogs and see if it stays within good AFR's.


Any tuner working with a boost controller/solenoid will do a baseline off the wastegate to see where the starting point is.
i have not, how would i go about doing that??

i remember my tuner pinching one of the vacuum lines to the wastegate at the very beginning of my tuning session once.
 

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i have not, how would i go about doing that??

i remember my tuner pinching one of the vacuum lines to the wastegate at the very beginning of my tuning session once.
Run boost source straight to the bottom port on the wastegate. This way you will only run the rated spring pressure PSI setting, whatever that may be.

Make sure nothing is blocking the top port, or that it can breathe freely.
 

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also, might be worth mentioning, when i put my car into accessory mode and the fuel pump primes, i can also hear a loud click from the solenoid. Is that normal? ive never really noticed it doing that in the past before..
Was your old boost controller wired in before you got it tuned? If not, then you wouldn't hear anything in that case.

If you did have it wired up before getting it tuned, did you not notice the "click" at that time? You mentioned you changed the solenoid in an attempt to fix your boost issue. I have noticed a big difference in sound between two identical MAC solenoids used in similar setups. One will be quieter than the other, no particular reason why, just manufacturing differences. It could be as simple as that, the new one is just making more noise than the old one.

That click should just be the ECU cycling certain outputs as normal during the key on phase, although testing will be required to determine what "normal" is. I haven't paid that much attention to my setup honestly, and my solenoid is already stupid quiet.
 

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Discussion Starter #12
Run boost source straight to the bottom port on the wastegate. This way you will only run the rated spring pressure PSI setting, whatever that may be.

Make sure nothing is blocking the top port, or that it can breathe freely.
so what i ended up doing is running BOTH the bottom and top port directly from the turbo. I set a boost cut somewhere around 18psi and sure enough my boost was able to reach 16 no problem before i let off to prevent it from hitting the boost cut..

so this definitely means something's wrong with the solenoid, its staying open for an odd reason.

The valve inside the solenoid is functional however. i disconnected my MAP sensor and it started buzzing like crazy. so my only guess now is that there's something wrong with the circuit in my ecu.
 

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troubleshooting is necessary.

Now that we know it is at least solenoid related, you can do some simple tests, such as wiring a small LED or lightb ulb to the power wire of the solenoid, and see if it flickers at all.

Else sounds like your tuner will take care of you.
 

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Discussion Starter #16
troubleshooting is necessary.

Now that we know it is at least solenoid related, you can do some simple tests, such as wiring a small LED or lightb ulb to the power wire of the solenoid, and see if it flickers at all.

Else sounds like your tuner will take care of you.
we'll see what happens, he told me there's only a handful of reasons why it could be doing this so hopefully we get the the bottom of this :)
 

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Discussion Starter #17
alright, so quite an interesting finding here.

So this is my third solenoid that ive put in the car. The first one died on me completely and it was running around 74-75% duty cycle when under boost at 23psi. The second one i had, which was the one i just replaced, was around 70% at the same amount of boost.

When doing a quick session with my tuner, we ran a couple tests and determined that the solenoid was infact working. Nothing was wrong with the circuit whatsoever. The problem however was the fact that since my tune was still running on the last solenoid's duty cycle, for whatever reason it wasnt enough for this one to hit the same amount of boost.

So long story short, 70% duty cycle was enough for the last solenoid to maintain 23 pounds, but this one requires 75% to maintain the same boost. Much like the first one that died on me.
 

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alright, so quite an interesting finding here.

So this is my third solenoid that ive put in the car. The first one died on me completely and it was running around 74-75% duty cycle when under boost at 23psi. The second one i had, which was the one i just replaced, was around 70% at the same amount of boost.

When doing a quick session with my tuner, we ran a couple tests and determined that the solenoid was infact working. Nothing was wrong with the circuit whatsoever. The problem however was the fact that since my tune was still running on the last solenoid's duty cycle, for whatever reason it wasnt enough for this one to hit the same amount of boost.

So long story short, 70% duty cycle was enough for the last solenoid to maintain 23 pounds, but this one requires 75% to maintain the same boost. Much like the first one that died on me.
that's good it got solved,.time for panty rippers?

the solenoids used ,,same make model ?
 

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Discussion Starter #20
I was also curious about this /\/\/\.

Glad you got it fixed, but could you or your tuner determine any particular reason the original solenoid failed?
im guessing just regular wear or something, it was on the car for close to 5 years!
 
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