Nissan B15 Problem

[grad]

I know this is very long but i am trying to be as detailed as possible, as this problem has been irking me for some time now.

I recently took my fiance's B15 to rebuild the transmission as on mornings, when the car is cold, it would need to heat up and build pressure so that the gear would go in. This would normally take about 10 to 15 minutes of heating up before the gear would actually go in.

We took the car to a reputable transmission mechanic in Ramai trace and asked him if we should rebuild or just swap out a foreign used transmission. We were advised to rebuild the transmission as "these transmissions don't normally give no problems". We gave him the car and he rebuilt the transmission and the problem of the car taking so long to heat up on mornings was gone. (the bill was a whopping 3800, but we thought our problems had been solved so we didn't mind)

So, after driving the car for a week, a new problem surfaced. When the car reaches about 30 to 50 kmph the car revs off with no acceleration and after a second or two then the gear goes in. Sometimes the gear would slam in. This problem happens sometimes not everyday. We took it back to the mechanic he said "what he fix in the transmission is good and that would give no problem" he advised that after re scanning the car he sees no problems and he kept it for a couple days with no indication of the problem. He then advised that it "could be" the sensor, the throttle body, something shorting or "Problem X that will always give that trouble" (I don't know if anyone buys or fixes a car with the expectation that it will always give trouble)

Nevertheless, we serviced the throttle body, then eventually replaced the electrical part of the throttle body (as he mentioned the shorting) changed the sensor. The problem still exists.

We took it to another transmission mechanic, he changed the solenoids for the 2nd gear and the entire valve body, and still we are having this problem. This mechanic said the only thing left to change is the computer given all that we have done so far.

I am kinda skeptical that this may actually work, but nevertheless after all these parts and changes we still have this problem. Has anyone had this problem and knows the fix given all that has been done with the car?

Thanks

[skylinechild]

i am not a transmission specalist however it seems that these ppl are just taking you for a ride.

things ive learned watching how certain "specialists" work.

1. they have the cheapest scan tool - it may not read all errors / trouble codes

2. they "assume" thinking this is the problem

3. they apply the fix for the wrong issue

4. they supply the cheapest of the cheap parts - ie f. used give no warranty but charge a premium.

from what you describe - all the symptoms point towards the TCU (transmission control unit) / solenoids

you said you replaced 2nd gear solenoid however these (solenoids) not designed to be replaced individually - these come on a wire harness and designed to be replaced as a pack (or kit) - ie all 5 solenoids.

the solenoid kit contains the following solenoids

shift solenoid A
shift solenoid B
line pressure solenoid
torque converter solenoid
over drive solenoid.

i recently had my transmission fail while at my technican's garage - NOT due to anyything he did ....lol.
he checked through the system and correctly diagnosed the issue and gave me options.

i ordered the new transmission solenoid kit - a new metal screen transmission pickup strainer - and a new sump pan gasket - all from japan.......and for good measure a new B&M oil cooler from amazon.

The tech did the installation and such.....since getting the new parts ..the transmission feels like new...very smooth shifts.....acceleration is on point...kick down as well.....

my bet is something with the solenoids - get a new solenoid kit and work from there.

[grad]

Thanks skylinechild for the detailed response.

Well, I was there when he took out that single solenoid from the harness. Yes it looks like it is an entire harness and should be changed as a whole. However, he did do a very neat job. You could not tell that he had changed it. If i remember correctly it was the one with the red wire. We even tested each solenoid with the multi-meter and everything worked out fine.

Nevertheless, your reasoning sounds logical and replacing the entire kit would definitely be on the cards.

[skylinechild]

Thanks skylinechild for the detailed response.

Well, I was there when he took out that single solenoid from the harness. Yes it looks like it is an entire harness and should be changed as a whole. However, he did do a very neat job. You could not tell that he had changed it. If i remember correctly it was the one with the red wire. We even tested each solenoid with the multi-meter and everything worked out fine.

Nevertheless, your reasoning sounds logical and replacing the entire kit would definitely be on the cards.

before you spend money again..contact ryotech performance aka ryan.
he's a powerseller on the forum and hes the tech who correctly diagnosed and resolved my issue.

his scan tool will be able to identify all errors on the TCU and check the solenoids themselves.
have him do a scan and see what turns up. scan and diagnostics souldnt be much.
his contact info is on tuner - do a search for ryotech performance.

be warned a new solenoid kit is $3720 from steal and massey and theres none in stock. (AFAIK)
if you going the solenoid route you'll also need a new sump pan gasket - youre not supposed to use silicone to seal the sump as if the silicone gets into the valve body and the solenoids you'll be buyin a new valve body and solenoids - AGAIN.

the pick up strainer in the sump pan is a metal screen filter - it can be cleaned with a spray tin of brake clean and set out to dry and be reused.

i can put you onto someone to get the sump pan gasket and pick up strainer NEW - OEM nissan- if you like - as steal and massey didnt have it.

i opted for a new strainer as some debris may be small enough to be lodged in the strainer and then when you use the strainer it goes back into the system and gets lodged into the valve body or worse - the solenoids.

[grad]

Thanks skylinechild for the detailed response.

Well, I was there when he took out that single solenoid from the harness. Yes it looks like it is an entire harness and should be changed as a whole. However, he did do a very neat job. You could not tell that he had changed it. If i remember correctly it was the one with the red wire. We even tested each solenoid with the multi-meter and everything worked out fine.

Nevertheless, your reasoning sounds logical and replacing the entire kit would definitely be on the cards.

before you spend money again..contact ryotech performance aka ryan.
he's a powerseller on the forum and hes the tech who correctly diagnosed and resolved my issue.

his scan tool will be able to identify all errors on the TCU and check the solenoids themselves.
have him do a scan and see what turns up. scan and diagnostics souldnt be much.
his contact info is on tuner - do a search for ryotech performance.

be warned a new solenoid kit is $3720 from steal and massey and theres none in stock. (AFAIK)
if you going the solenoid route you'll also need a new sump pan gasket - youre not supposed to use silicone to seal the sump as if the silicone gets into the valve body and the solenoids you'll be buyin a new valve body and solenoids - AGAIN.

the pick up strainer in the sump pan is a metal screen filter - it can be cleaned with a spray tin of brake clean and set out to dry and be reused.

i can put you onto someone to get the sump pan gasket and pick up strainer NEW - OEM nissan- if you like - as steal and massey didnt have it.

i opted for a new strainer as some debris may be small enough to be lodged in the strainer and then when you use the strainer it goes back into the system and gets lodged into the valve body or worse - the solenoids.

spoke to ryotech on the weekend he said to call Monday. We will see how it goes and will review here as well.

[10k]

did you get tru with this issue? having a similar issue

[TurboSingh12]

And it would have cost you $1500 for a transmission and $400 for the tranny brain

[clintus]

Qg15 engine and transmission so common now it would be advisable to cut your losses and just swap it out. At least u would have an old one for parts in case an issue arrive. Most common issue is reverse goes and that's an easy fix.

[skylinechild]

And it would have cost you $1500 for a transmission and $400 for the tranny brain

true but how long would a fused part last as opposed to a new part.??
in addition does it make sense to swap out an entire transmission just to get around one small solenoid kit.??
thats like saying you have an engine with a leaky distributor - bad oil seals- and to get around from changing the seals you replace the entire engine....

the new solenoid part cost is $167 USD when last i checked.
even at the current exchange rate (1us =6.6tt) the new part comes up to $1.102.2 TT

shipping from japan may cost you about 400TT.....

so it comes up roughly to the same...to why buy an entire USED transmission with 2 weeks warranty....when you can get a genuine new nissan part for the same cost??

i not sayin f used isnt good i'm saying look at all the options then decide what you can / cannot afford.

the only two ppl who really benefiting in this scenario is the f used place that sells the transmission...
and the mechanic who has to install it....
6 mths later when the same f used trans start up with the same thing again...?
what then..??
buy another trans and hope for the best ????

[racedriverpro]

^^ Well so far f used look like the best option since most mechs and diagnostic guys dont knw their ass from their elbow.. thats probably why many car owners are parts changers.

[skylinechild]

^^ Well so far f used look like the best option since most mechs and diagnostic guys dont knw their ass from their elbow.. thats probably why many car owners are parts changers.

correct. some ppl just called a mechanic as a name cause they have a garage filled with tools and cud change a transmission in less than an hr.

throwing parts at something and hoping the problem is solved isnt the way to get the issue fixed.
as cars become more and more modern slowly but surely ppl starting to catch on about proper procedures and diagnostics....but of course there will be those who feel cause they have a scan tool they is the best thing out.