“VOLVO MAF” conversion 1997 to 1998 3.4, supercharger upgrade,

Excellent, if you run into an issue I would stay with the OEM DESNO electric parts from 02 sensors to the MAF sensor to engine knock sensors if those needed to be replaced

 

Yes I was schooled on that by a friend and most excellent is ims passed got my plates!! Man this this upgrade save me $ thanks! I bet the previous owner would be bummed if he new what I saved and what it took to fix it !

 

Mod complete. Took all of about 30 min. Repinned exactly like @1997tacomav6 (same wiring).

Took it for a quick spin. Noticed LTFT moved a little more positive than it was with the old maf (9 to 14). No CEL or anything. I’m assuming because the MAF is less restrictive, it’s picking up more flow so the ECU is trying to compensate as it’s calibrated for the restrictive MAF?? Drives about the same. Didn’t really get a chance to push it hard though.

Over the course of the next week I’ll monitor my MPGs on my usual trip to work and see if I notice any differences.

Overall good mod. Cheap and easy. Feels good knowing I can clean my MAF easier and replace it for much cheaper if it fails.

 

You probably should reset the ECU so it will relearn the new part, pull the fuse for ten minutes

 

Forgot to do that. I’ll pull it now. I noticed a guy on TTORA had a slight shift up in LTFT after the mod as we’ll so I figured it’s normal.

What’s your SG report for your LTFT??

 

Don’t have that option available I think

 

Do you have a scanguage II?

 

Yea. You gotta go to their website and find the code and enter it in the x gauge feature

 

I'm surprised you aren't monitoring your LTFT's. Since you're spraying methanol without any engine management, your ECU is going to be fighting to maintain stoich AFR(~14.8) while you're spraying to bring the AFR's down. Your LTFTs are going to be all out of whack. That's why the AEM FIC lets you skew MAF voltage input into the ECU and you maintain pretty much 0 LTFTs.

 

Just talked with scanguage and they do have that x option available for me that has to be programmed,
didn’t know that.
She said I need to enter 6 program numbers for each bank for long term and 6 more for short trims.

Do the fuel trims read as an average for all the bank or each? Do I want short trims or long trims or both?

 

The 1st gens just have one AF sensor between the two banks.

Good to monitor both but really LTFTs are going to show the long term readings which are useful. STFTs can be helpful when diagnosing but they do fluctuate quickly as expected based on driving conditions too.

This is a great post that explains it well. https://www.tacomaworld.com/threads/understanding-o2-signals-and-fuel-trim.259164/

 

Thanks, good info,

So the gal was a little confusing for me that I talked to at scanguage.
For the v6 there are two banks? Left and right I’m assuming?
She was telling me I needed to input all the info from this page to program it.
Original I thought she said 6 banks of info.
Bank 1,2,3,4 for short. and
Bank 1,2,3,4, for long.

I’m guessing I put in just bank 1 and 2 info for programming?

 

Got it figured out, scanguage rep said 1 of the 4 bank program numbers will work trial and error one at a time.


Start with bank 1 program numbers and keep going till one of the 4 bank program numbers work for the scanguage to activate The fuel trims info

 

I always monitor LTFT. Says a lot about how the engines operating.

 

Glad you got it figured out. I am not familiar with how to program the ScanGauge. I use a Bluetooth OBD2 reader and view the data on my phone through OBD Fusion.

So what are your LTFTs?

 

Don’t know, I’m off to a wedding 6am tomorrow and won’t be back for 4 days, then I will program it and hopefully get it to work

 

No it's doing that because the MAF measures inaccurately in a tube that isn't the diameter it is designed to meter air through. I have said this before, and people don't seem to believe it but this mod is a hacky way to go about changing this part. I totally get the want to save money on an expensive part and for the SC folks to reduce intake restriction. But this mod without K-level correction in the ECU is just making your computer work harder to correctly calculate fuel mixtures because it is being fed incorrect data. In closed loop that is fine I suppose even though you move yourself closer to a CEL trigger, but in open loop it is likely running too lean because in open loop it doesn't use the O2 to help trim out all the fuel inconsistencies the fuel table is being reference for because of the incorrect airflow it is seeing. The MAF and its associated tube is not some generic part to be swapped around unless you are a tuner with a tunable ECU that you can calibrate for certain sensitivity and voltage curves. When you do a mod to your truck and see that it influences fuel trims but the influence didn't bring them closer to a 0.00 reading, it's a good indication that what you have done is not in your best interest or the EFI system's.

I have voiced my concern on this mod before and really I hate to rain on anyone's parade, but having knowledge of how these systems work and how they are modified in the aftermarket with tunable ECUs I would feel wrong if I didn't say this is really the wrong way to approach this "problem"

 

I have thought about this I can see how to much air can be a problem. So I ordered a tunable MAF tube just in case. Should be here tomorrow. I’m not a pro mechanic by any means. Everything is working great so far for me but I have know way to really know 100% for sure .It would be nice if someone had some before and after numbers.

 

Not raining on my parade!
It’s obvious you know more than most but obvious your not aware that
both MAF tube sections, Volvo and stock OEM are actually the exact same width across at the widest point that being 3” making this an excellent swap for me.

With this swap it’s been all positive for me.
Couldn’t be happier with it.
I’m getting 3 mpg more or so
Gained 1/2 a pounds of boost.
Truck has more peep.
My truck has had zero issues from this swap, zero codes,
AFR are perfect shown on a professional dyno machine and all that with 35,000 miles of road time and supercharged more than a year later.

The reality of the comparisons for dimensions of these two MAF tube sections are that they are the same size (Max) across maybe 1/8” different on the throttle body side at 3”.
The air filter side is where the Volvo is larger across and the OEM Tacoma is smaller.
An increase in airflow for the Volvo would be because the bullet is not there anymore and the air box side of the tube is larger, but most importantly the inside wall is the same distance across on both the Volvo and OEM tube sections where the MAF sensor is located.

If the Volvo section was an inch wider 4” across or even 3.5” the entire length of the tube than the OEM tacoma at 3”, I understand and agree but it’s not, it’s the same size,
Both MAF sections are 3” across at the widest points.
The Tacoma OEM tube section is approximately 5” long and most of this length of tube section is 3” across.
There is an inch and a half or so out of the 5” that is smaller on the OEM tube across that connects to the air box before the MAF sensor.


All thumbs up for me.

 

Bank 1, first gens only have one bank