First of all thanks for any time and advice from the club. I just recently acquired an 87 TII with a low mileage great compression motor. So far I have installed a banzai block off kit as well as OMP block off, 720cc EV14 injectors, and an Rtek 1.8.

When i first installed everything I installed the rtek and did a shitty job unknowingly. It ran but had no throttle response after 2.5k. So I checked for codes and it continuously blinked showing the rtek was a fail. So I reinstalled it in another n332 ecu and the flashing stopped but now it wont even idle. SO I assumed I burned the rtek chip itself. So I bought an rtek 2.0 tuned to a 1.8. No difference.

Without touching the pedal it will fire and rev to 400rpm or less and die. if i give it a little pedal i can feather it to run for a little while then it again dies. Ive checked for vacuum leaks and missed harnesses.

When i try to adjust the tps something seems weird. when i go to connect the LED lights to the harness my duty solenoid and the other 4 start clicking.

Needless to say my level of confusion is insane

 

you know you have to run the Afm right?..is it hooked up?

 

yeah the afm is plugged in. i thought maybe it was the high impedance injectors so i eliminated the resistor block like your supposed to and it helped slightly ut it still wont run by itself.

I think maybe my leading coil pack is somehow bad. when put the timing light clasp around the plug wire on the leading plugs it blinks really fast as it should but then it will have a full second of solid light periodicly. The trailing seems fine though. When i do get it running its extremy rough and sounds almost as though only one
housing is getting much spark.

My next question is, is there a difference between n/a and turbo coil packs ? Cause if not ive got a set. I would search but I am on my phone at work and the damn search option wont work.

 

N/A and TII coils are the same,so they are interchangeable.

 

And make sure the spark plug wires are in the proper order and going to the right plug.

 

sweet,

i have an NA set in the garage. I will update this evening.

 

Replacing the leading coil helped slightly, its easier to keep the rpms around 2k to keep it running now. Still wont run by itself. I'll add more grounding straps today.

 

If the car can idle, put a timing light on every wire to confirm consistent spark. 400rpm is low, but you should see the notch within range.

Test every plug wire. Ensure the ohms are within spec per FSM.
Use the FSM to test the AFM, CAS, Air intake temp. Make sure all contacts and plugs are clean.
Test for proper base fuel pressure.

You'll get it bud. Getting closer.

 

AFM was bad, but did not show any codes. Swapped it this morning now it's running great.

 

It just shows how little self diagnosis the FC's have. Great job bro. I hear its pulling hard too.

 

An AFM caused all your problems?

 

a faulty airflow meter will do tons of things.

it will allow the car to run the warmup sequence and then for a couple secconds be fine, and then conk out and die.

it will also prevent the ecu or the coils themselves from fireing even though they both check out fine.

it does one other freaky thing, but i cant recall off the tip of my head. yeah, afm sucks.

 

Bravo to you sir. Glad to see someone who seeks advice, follows it and has their problem solved. Noobs take notice.

 

is it a revolution? i think noobs are the ones taking advise because they are excited to work on their car. some people dont really wanna bother and would rather fix one thing and have it fix all their problems.

 

I wish that were the case, but there is plenty of evidence to the contrary...

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/help-event-weekend-car-acting-up-first-time-bogs-when-flicked-999161/

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/rtek-1-8-4-x-750cc-injectors-apexi-neo-maxed-still-lean-under-wot-997235/

 

yes sir it infact was the afm.

lol thanks sharingan. im not exactly a noob to rotary tho.. just a noob to the club i suppose. I grew up with XLR8, steelemotorsports, and bob13bt on the club. Rotary is what they know. lol They are like my TII spirit guides.

back to shop talk.

I still have a few issues I am working out. Coolant pressure which i found the culprit....a misrouted overflow line from the former owner. Also an extremely low idle ( near 500rpm). ive been scoping related issues and it seems i must have a vaccuum leak. im going to do the 3k rpm test for sputtering tonight to confirm it. with no bac valve i may just reallly need to adjust it farther.

thanks for replies, advice, and the compliment !

 

s4 t2 and na afm the same?

 

yep.

 

diff part numbers!

 

Wait, what?! NA and TII AFMs are not at all the same. A TII will run with an NA AFM, but the signal to the ECU is different. You'll blow your engine running an NA AFM in boost.

 

Someone call the spirit guides, lol

Actually I wasn't calling you a noob "noobs take notice" was a call for all noobs reading the thread to observe how the process is supposed to go. However....the above statement is causing me to question my initial judgement

Also, please get a BAC, anyone who doesn't have either a BAC or a stand alone is an idiot imho.

 

look for an S4 N318 Afm.That is what you need.

 

i don't know about running an n/a AFM in a turbo causing the engine to pop but it will max out at lower power levels due to the weaker spring and cause the engine to run richer than necessary.

i have seen more botched turbo engine swaps than i would like to acknowledge.

it works for diagnosis and to get the car running and drivable in a pinch but i wouldn't leave it in there.

on the flipside an n/a won't run very well on a turbo AFM because it will run severely lean.

 

The voltage output at max deflection is lower on an N/A MAF compared to turbo.

 

That's backwards. Once you max out the AFM, the ECU has no way of knowing that airflow continues to increase, and does not add more fuel to compensate. You end up with a lean mixture at high RPM if using an NA AFM with a TII engine. You have to have some way of adding fuel manually.

Here's an NA AFM on an engine with a small hybrid turbo @ 10 psi. The AFM maxes out at 715 kg/hr (26.3 lbs/min). https://www.rx7club.com/showpost.php...&postcount=229

Notice the airflow measurement stops climbing at ~5000 RPM, and then it's just a flat line to redline. I don't know what his fuel corrections were at the time, but you can watch the AFRs climb as soon as the AFM maxes out.

I've datalogged my stock turbo hitting that same airflow at 4700 RPM and 12 psi, and 5100 RPM and only 9 psi. You might be ok if the engine is bone stock making stock boost.

My V-trim hybrid will hit that airflow at 4500 RPM and 12 psi.