Will not idle unless throttle is all the way to the floor

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roger1079
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Will not idle unless throttle is all the way to the floor

Post by roger1079 » Sun Sep 02, 2018 12:51 pm

Hey everyone. First off I want to thank everyone who contributes to this site. You guys are absolutely amazing and I wouldn't be where I am now without this incredible resource. That being said, I finally feel like I am close to getting the car to turn on and idle however I've hit a wall and no amount of searching and reading is helping at this point.

A brief history:

It is a 1992 Mustang GT 5spd swap (A9P still installed, Moates QH). The car has just undergone a huge amount of mods including swapping the Tweecer R/T for a QH.

331ci Dart Sportsman shortblock (9.0:1), AFR 205's, Custom Comp hydraulic roller cam .577/.557 112, Trickflow 6.5 pushrods, 1.6 rockers, Vortech SCi pullied for 17psi, Aeromotive A1000 Stealth fuel system, Deka 60lb inectors, Victor intake, 75mm t/b, MSD ignition, longtubes, no cats, and a 77mm Pro-M metal MAF calibrated for 24's. The car ran prior to the latest changes and not since.

Currently I have replaced the coil, distributor, TPS, and have verified timing, spark, and fuel pressure (41psi). Currently the car will turn over and start however I must turn the key at part throttle and as soon as it turns completely I have to depress the pedal to the floor where it will hold a very rough and unhealthy sounding idle around 800. As soon as I begin to lift my foot the car instantly turns off. I am currently using the A9L base as I feel it is easier at this point considering I do not have a full understanding of the A9L2 changes. I took about a minute datalog sample this morning with my foot to the floor and the car idling unhappily. I am in hopes this is something simple I am just missing as a novice. I am attaching both the tune and datalog file in case somone much more experienced than I am may have some insight. The car has been off the road for 4 years now and I'm dying to get it back out of the garage so I can continue learning. Thanks in advance!
Attachments
A9L_090218 2018_Sep_02_10-29-52.csv
(516.12 KiB) Downloaded 4 times
A9L_090218.BIN
(56 KiB) Downloaded 4 times

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Paulie
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Re: Will not idle unless throttle is all the way to the floor

Post by Paulie » Sun Sep 02, 2018 1:15 pm

I took a brief look and do not see anything obvious in the tune. I would suspect a mechanical issue. Ignition timing, firing order or bad fuel. Have you checked compression? Also check all your intake tubing. Possibly even a vacuum leak.
1990 Mustang 5.0, HCI, Vortech S-trim, FRPP 42# inj., PMAS MH95, A9L, Moates Quarterhorse, BE/EA, Innovate LC-1.

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EDS50
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Re: Will not idle unless throttle is all the way to the floor

Post by EDS50 » Sun Sep 02, 2018 4:00 pm

I would advise sending your meter in to be recalibrated for the injectors and ecm you are using or upgrading to a pro-m 80 calibrated properly.. Using a auto computer with a stick conversion without changing the o2 harness usually results in burning the traces on the ecm board; add the fact that you are using an a9l.bin on the a9p ecm is a recipe for disaster. The maf curve you have in your tune is not even close to being correct for the meter you are using which will be too small for what you have anyway. Try to stay away from that a9l2 garbage, you wont find much if any support for it here.. Your tune can use some help but you need to verify all the mechanicals are sound first. Is the distributor installed correctly? How are the rockers adjusted...etc...etc...You mentioned the car has been sitting for 4 years...you have fresh gas in it? You check the tank and lines and pump to make sure nothing is deteriorated? You mention you switched to a QH, is it new or used? When is the last time the battery was replaced on it? Lots of questions that need to be answered...
1992 LX - 25.1c Chassis, Vortech Blown Dart 332, Lentech Trans, TRZ Backhalf, A9L, Moates QH/SL v1.9, BE, EA, TunerView

roger1079
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Re: Will not idle unless throttle is all the way to the floor

Post by roger1079 » Sun Sep 02, 2018 5:20 pm

Paulie wrote:
Sun Sep 02, 2018 1:15 pm
I took a brief look and do not see anything obvious in the tune. I would suspect a mechanical issue. Ignition timing, firing order or bad fuel. Have you checked compression? Also check all your intake tubing. Possibly even a vacuum leak.
Compression is good, timing is good, and firing order is good. I was also unable to find any vacuum leaks. Bad fuel could definitely be the culprit though as the car has been sitting a long time even though I did add stabilizer to the tank.

roger1079
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Re: Will not idle unless throttle is all the way to the floor

Post by roger1079 » Sun Sep 02, 2018 5:33 pm

EDS50 wrote:
Sun Sep 02, 2018 4:00 pm
I would advise sending your meter in to be recalibrated for the injectors and ecm you are using or upgrading to a pro-m 80 calibrated properly.. Using a auto computer with a stick conversion without changing the o2 harness usually results in burning the traces on the ecm board; add the fact that you are using an a9l.bin on the a9p ecm is a recipe for disaster. The maf curve you have in your tune is not even close to being correct for the meter you are using which will be too small for what you have anyway. Try to stay away from that a9l2 garbage, you wont find much if any support for it here.. Your tune can use some help but you need to verify all the mechanicals are sound first. Is the distributor installed correctly? How are the rockers adjusted...etc...etc...You mentioned the car has been sitting for 4 years...you have fresh gas in it? You check the tank and lines and pump to make sure nothing is deteriorated? You mention you switched to a QH, is it new or used? When is the last time the battery was replaced on it? Lots of questions that need to be answered...
I am leaning towards replacing it. It is a very old 77mm Pro-M in the metal housing with cone filter. As far as the stick conversion, I didn't even know it was an auto car when I bought it until the Tweecer went in. My understanding is so long as the auto computer is retained, the existing o2 harnesses would be compatible. I did read that burning traces on the EEC is almost certain if using the auto o2 harnesses with the A9L. May i ask why using the A9L bin on the A9P is not recommended? My understanding is also that with the Quarterhorse, using a different bin is fine as long as the correct strategy is used. As far as MAF curve, I used the Prom-24 curve from EA. After reading your post, I'm almost certain I'm going to replace the meter with the correctly calibrated unit just to assure it isn't the issue and to get an accurate flow sheet. The distributor is 100% installed correctly and brand new as I needed to rule out the PIP sensor and the Cardone OEM replacement unit was only $79. The rockers are adjusted correctly and the gas in the car has only been sitting for about a year with freshly pumped 93 and stabilizer added at the time of fillup using gas cans. As far as the fuel system goes, it was all replaced 1.5 years ago with an AEM stealth kit. The only remaining parts of the previous system still in place are the filler neck and injectors. Everything else is brand new. The QH was also bought new. The battery is a 5 year old Optima red top which has been connected to a battery tender with trickle mode the entire time the car has been garaged.

Thank you for taking the time to help a newbie out. You have no idea how much it is appreciated. I am absolutely not new to turning wrenches, however tuning is new to me now that I have gone well beyond injector slopes and turning off emissions parts that were removed.

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EDS50
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Re: Will not idle unless throttle is all the way to the floor

Post by EDS50 » Sun Sep 02, 2018 6:38 pm

Sounds like most of your issue is going to be contained to your meter and tune since you are confident about the mechanicals which is good. You mentioned you loaded a 24# calibration which would be fine if you had 24# injectors but since you have 60# and are using what I assume are the motorsport specs for the injectors in the tune you will need to try improving the maf transfer. I don't know where you pulled the 24# transfer from but if its from a reliable and accurate source, try multiplying the maf kg/hr values by 2.5 and try starting the car again after clearing the kamrf's (learned fuel trims). As far as using the a9p with a stick, the o2 harness is wired differently as well as the neutral safety. Since you are running a 5 speed transmission, your loop on the back of the 02 harness needs to connect a blue/yellow wire to a purple/yellow wire. Look at how the harness is setup now, it should have a looped wire on the back of it. The loop is either purple/yellow or blue/yellow. The AOD harness should be connecting a white/pink(or purple), to a purple/yellow wire which is what you dont want when its converted to a 5 speed. You can re-pin the harness if you need to unless it was already done by the previous owner. Who knows, try the maf transfer first.
1992 LX - 25.1c Chassis, Vortech Blown Dart 332, Lentech Trans, TRZ Backhalf, A9L, Moates QH/SL v1.9, BE, EA, TunerView

roger1079
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Re: Will not idle unless throttle is all the way to the floor

Post by roger1079 » Mon Sep 03, 2018 6:33 am

Gotcha. I had my info confused for the o2 harnesses. The neutral safety was bypassed/missing when I bought the car (it will start without the clutch being depressed). I know that isn't safe, I just have made it a habit as long as I have driven a stick to always check the shifter is in neutral and that my foot is on the clutch. I'll get under the car and verify the o2 harness today as I just repaired the 3 caps in the EEC. I've been proficient at soldering most of my life and did this myself, so I also thought I may have not gotten something quite right with the coating. I have pulled everything apart, checked all solder points with a meter at the resistor and checked for continuity at the next trace and all is well. All resistors were resoldered in the right flow direction and the pump primes for 4 seconds when the key is turned as well as primes when the distributor is turned with the key on, engine off. I have been shopping for any compatible replacement and cannot find one anywhere except eBay where the prices are offensive considering these computers were less than $200 with core a couple years back.

I got the MAF Transfer from 2 places and compared. The first was from the preloaded transfer in CalEdit for the Tweecer and when I had further issues, I got the Transfer from the preloaded curve in EEC Analyzer. They are both labeled as for the ProM24 match 100% and I consider both to be trustworthy. It is also worth noting this meter worked perfectly on my previous 94 and has been in a box in the attic since it came off that car, so I know it was a working unit the last time it was used even though the last use was with injectors calibrated for it. I know there is potential for problems at the top end since the meter is callibrated for injectors barely more than 1/3 the flow of the 60's, and had a new meter on the list even before the, I just want to get the car started and idling at this point so I can verify guages, complete burping of the coolant, etc. Thank you again for the help!

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EDS50
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Re: Will not idle unless throttle is all the way to the floor

Post by EDS50 » Mon Sep 03, 2018 7:27 am

The maf transfer function you are using is for a pro-m 75mm bullet. Try my recommendation with the transfer and you may also need toplay with the injector slopes to get the car started. What do you have your plugs gapped to and what kind are they?
1992 LX - 25.1c Chassis, Vortech Blown Dart 332, Lentech Trans, TRZ Backhalf, A9L, Moates QH/SL v1.9, BE, EA, TunerView

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