When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
MS2 Tuning Help! Wont idle, hard cold start, no tach, fuel pump runs all time time.
Hey boys and girls. This car has been sitting since about 2012 when I parked it and went back to school. Now I've graduated and want to finish it and drive it before I start working a new job
I'm piecing this car together from my 4 cars worth of crap that I collected over years of owning in Miatas. I was in school and havn't looked at it in years. I was an new with MS2 then, I'm full on idiot now. I'm in WAY over my head.
Car:
Rev Enhanced MS2 (he still around?)
1990 Miata
1.8 Engine
99 Head
NA Manifold
1.8 Throttle Body
1.8 Coils 94/95
Sequential Injection
LC1 Wideband
Speed Density - Temp Sensor is threaded in bottom of intake manifold, AFM is there for looks and I will delete it soon.
Cold Start: Surprisingly, it started up right away this time. Usually the engine cranks and sputters. It does not want to idle and died right away, and was hard to start again, which is the way it is usually on the first start.
How do I get my tach to work? I've tried the resister between B+ and IG- with and without a wire connecting the 1.8 coils to the factory 1990 tach via the blk/white at the 94/95 coil to the yel/blu at the cluster as per my wiring diagram and STILL no tach!
What do I need to do to make this thing idle and start better?
How is the tune in general?
Anyone in Sacramento area (or bay area) want to take a look and mess with it? Any shops anyone would recommend when I get some money to tune?
Last edited by Mysticle31; 01-28-2017 at 01:29 PM.
I drove it today. All the same problems. Cold starts like an cold old diesel tractor, fuel pump runs all the time, no tach, wont idle (hard to catch), and need a tune.
1. the ignitor usually drives the tach, could be damaged, but then swapping on 94/95 coils could also be to blame.
2. tune.
3. from the read of it, not well.
4. 18psi.
Hey Guys. Didn't want to start a new thread. I'm back to working on this again. First problem to solve isn't the tach or any "small" stuff. It's the WBO2 and a smog check.
Problem at hand. Bouncy AFRs. If I can get the AFRs/WBO2 under control I think that will solve a lot of the issues I'm having.
Attached MSQ and Datalog. You;ll see at idle it seems fine then when I rev the engine it swings AFRs all over the place. I just did a free air calibration with the sensor in the car.. The car has been off for a week or so.
The plan to fix it is to remove the WBO2, do a free air, and check out it's config in LogWorks. I have an AEM UEGO standing by to go in if that doesn't work. For today and tomorrow I have access to a 5-gas. Should the WB02 and the 5-gas agree on O2%? Even if the 5-gas is sampling after the cat, and the WBO2 is before the cat?
Do you see anything obvious that I should fix? Why is it doing this? It's pretty intermittent. Sometimes it's fine, and sometimes it's not. More often not.
Datalog: https://drive.google.com/file/d/1lZA...ew?usp=sharing
Ok, I see a few things that could be problematic;
- Overrun fuel cut starts @1400 RPM when MAP <28kPa and CLT > 105.8
That means that if you go just a bit beyond idle (>1400 RPM) and then lift (MAP < 28 kPa), then all fuel shuts off and your AFR will go crazy lean. You might want to raise the RPM limit, lower the MAP limit and raise the activation temp for when the engine has warmed up.
- EGO Control starts @500 RPM w/ 25% authorization
Your EGO control is fighting the CL idle PID loop, there's no telling which one is "winning". You should raise the RPM activation, and (maybe) lower the authorization to 10% or less - if you have to correct by more than that, your VE table needs attention.
- Set your Priming PW to all zeroes if you don't want the fuel pump to come on when you turn on the key.
Some other things to consider;
You might want to turn off CL Idle until you can start the car successfully and idle w/o issues
Ditto for EGO control until you can run (semi-) successfully on the VE table
Are you REALLY using Fuel Table Switching?
Did you calibrate your MAP sensor?
Do you REALLY need that much Time-based AE?
Your car actually starts w/ a 1* cranking advance?
Added; I never could get the LC-1 to work consistently. I have no experience with the UEGO but anything is better than the LC-1 IMHO.
Thanks. I'll look into that when I work on the car again. It will be a month or so before I'm back. I wonder if letting it sit for long periods of time is corrupting things. It wasn't doing this when I parked it a year ago.
I'll look into all you suggested and possibly redo the powers and grounds in a month or so.
01-27-2017, 04:25 PM
MS2 Tuning Help! Wont idle, hard cold start, no tach, fuel pump runs all time time.
0
