Woody needs EFI tuning

[AdrianS]

Hi there. Novice. Have done some research but can't seem to find exactly what I am looking for. Appreciate any help :)

I have a 1989 Jeep Grand Wagoneer (AMC 360 5.7L), previous owner installed Howell EFI kit https://howellefi.com/product/k247jw...-wagoneer-360/

Also has HEI distributor upgrade.

Issues observed:

1) fuel pump primes but still hard to start.

2) does not rev high and then settle.

3) often stalls after starting

4) can sometimes smell fuel after starting.

5) pops, sag, stall after accelerate off idle (intermittent).

6) error code 33 (low vac pressure) can be read from the engine warning light (paper clip trick) ...

Looking to use something like ALDLdroid https://www.aldldroid.com/ but this needs an ADX file and I have no idea where to locate the right one.

Appreciate any help for a novice looking to fix and tune my favorite car...

ECM is GM PN 1227747

Thank You

[steveo]

the manual for your swap kit says it's a 7747 GM ECM.

it later mentions using an 88 or 89 truck with engine E or K code when connecting an obd scanner. so i'd guess it's running $42 or similar

http://www.gearhead-efi.com/Fuel-Inj...Information-42

if you read that thread there are a few different ADX files for different manual or auto transmissions

try that first

[1project2many]

Welcome to the forum.

$42 is the correct code for a true Howell conversion. If the swap was done using junkyard parts you should locate the ecm and get the part number or service number to ensure you get the correct adx.

Feel free to post questions if you decide you'd like help with the diagnosis. Some questions to answer would include: Was the Jeep running correctly when you purchased it or are you chasing down someone else's problem?
Is the HEI distributor connected to the computer or are you using vacuum and mechanical advance?
Is the conversion a true Howell conversion? Is the Howell chip installed?
Have you chacked basics such as correct distributor angle and correct fuel pressure?

Good luck!

[AdrianS]

Thanks Steveo and 1project2many!

Looking at the thread from above I have fished out $42-1227747-V5.2.adx as this seems like the most recent $42 adx file (?) I think this is one to use with my car (3 speed auto).

The Howell EFI was installed new from a kit so I am pretty confident about the part numbers etc.

The car was refurbished, but done interstate, so whilst I saw the work at intermediate stages, it was shipped and I am dealing with the problems with good support from the refurb guy, but there's nothing like being at the car first hand.

I do not think the HEI is connected to the computer but will double check.

Yes to the chip question. This kit is specific to the Jeep GW.

Checking on the distributor angle and fuel pressure. I think the Howell manual says 12-15 PSI on the fuel line, so that is what I will check for. What angle am I checking for on the distributor?

Assume using the ALDL app is also a good way to figure out what is going on (with data from the available sensors)?

Many Thanks

Adrian

[1project2many]

The Howell EFI was installed new from a kit so I am pretty confident about the part numbers etc.

This is good. Howell used to be good about trying to provide support if you got completely stuck. If it turns out a Howell supplied component is bad you may be able to obtain replacement parts directly from Howell.

What angle am I checking for on the distributor?

The Howell conversions, especially CA approved conversions, are "fuel only" so the distributor will be set to factory settings. If there is no label under the hood of your vehicle with the distributor settings we can probably find them on the 'net.

Assume using the ALDL app is also a good way to figure out what is going on (with data from the available sensors)?

I hate to admit this, but my days of being interested in fighting new tech are slowly ending. I use the datalogging feature of Tunerpro with my laptop or I use TTS Datamaster. I find it easier to view data on the larger screen and I prefer to be able to review data on the same tool that I use to make changes. Maybe others can help with app choices.

[AdrianS]

Thank You!

I confirmed that the HEI (after market addition done with refurb) is NOT connected to the ECM -> is this a issue, and/or something to consider doing? Assume you can switch things over so the ECM also controls spark timing, and this sounds - in principle - like a good thing?

[1project2many]

ECM controlled spark timing imo offers more benefit than ecm controlled fuel delivery. I believe Howell does not alter timing because it makes their job much easier. I have looked at different Howell calibrations for I6 engines and the ones I have are not far from stock GM calibrations. I have not seen a Howell chip that alters spark timing even though the 4.2 Jeep engine is radically different from the 4.3 Chevrolet and 5.7 Chevrolet engines the chips came from. I believe that the easiest way to get your vehicle running is to ensure the installation matches Howell's instructions. I believe the best running engine will be achieved by switching to computer controlled spark but that will most likely require someone to do "real" tuning work to ensure the spark tables are correct for the engine.

Is the engine stock? If so, and if you've checked and confirmed all the basic settings, then it seems you have a choice. You can contact Howell and ask for help. They may offer to burn a new chip or they may have other tests they wish you to try. Or you can invest time and money in learning to adjust the calibration yourself.

Checking and confirming basic settings would include ensuring the sensors are reading correctly, setting the base timing, checking fuel pressure (which you've done), and ensuring there is proper spark.

[AdrianS]

Hi there, I got my ALDLdroid and OBD1 ECM reader working, and got a file but not sure how to interpret (as in I have all the columns and values, but not sure what normal values are vs problem values)... Only a short 10 minute drive and no real big issues, but I would really like to see whether there are any tell tale signs in there. Any tips/advice?

I can see some ERRORS and warnings in there, but not sure where to go next to diagnose. Any help appreciated.

Thanks!

[mecanicus]

"6) error code 33 (low vac pressure) can be read from the engine warning light (paper clip trick) ... "

have you already checked the vacuum lines to the map sensor?

[stew86MCSS396]

Hi there, I got my ALDLdroid and OBD1 ECM reader working, and got a file but not sure how to interpret (as in I have all the columns and values, but not sure what normal values are vs problem values)... Only a short 10 minute drive and no real big issues, but I would really like to see whether there are any tell tale signs in there. Any tips/advice?

I can see some ERRORS and warnings in there, but not sure where to go next to diagnose. Any help appreciated.

Thanks!

For starters, had issues opening spreadsheet with a windows laptop. Using LibreOffice opens up just fine. I'm not sure what's causing the code 33 as it appears to fall within the voltage range unless with key on engine off it's suppose to report 4.75 volts??? If so suspect a MAP sensor ground. BLM column suppose to be ~128 -/+3. Never seem to go lean but does go rich all the way up to 108 which is probably limited in the tune meaning it won't report anything beyond 108 if i.e. it's really 90. Same goes for your IAC it's limited to 145 so it's probably pegged wide open and wants to adjust beyond that but it can't. Perhaps setting your IAC might help...http://www.gearhead-efi.com/Fuel-Inj...-Fuel-Pressure

Okay...went back and watched some old 747 datalogs that I have...I maybe looking at the code 33 thing backwards. Well FSM says engine running at idle should be 1.1v but that's for an engine that idles ~30-35 kpa. One thing that may be amiss but it might be the way your logger interprets the data. Noticed that at idle TPS .51v and column next to it ~26% throttle. In TP .51v would report ~0% throttle. :shrug: