acefuture
Well-known member
- Jun 8, 2021
- 293
- 493
So as a few have seen, I picked up my new-to-me Alumicraft April of 2023. I was not in the market for a car like this, but was poking around for a 2 seat Alumicraft and this one presented the opportunity. 05 Alumicraft flatroof, with an LS3 525 controlled by a MEFI 4b, Albins AGB, Fortin Floaters, Billet spindles, all redundant systems, on board air, all the business. It's my absolute dream car and I was in the position to make it happen, so I went for it. I did some general off season maintenance over summer including all fluids, CVs, new trans pump, new filters, new shock hardware, hub services, etc etc. As I tore the car apart I was astonished at how well the car was prepped and how perfect all fluids and greases were. The car was built by Cooley in 2005 for Guy Evans (the owner of the one-off Alumicraft baja bug) to be a purpose built baja prerunner. The car has done just that and has many many trips from ensenada to cabo with little to no troubles between Guy and the second owner, guys business partner, who I bought it from. In 2015 it went back to Alumicraft and received a new bulkhead, front end, and big bumper. The car was parked in 2017 and had not been driven since.
When I bought the car, the only driving I had done in it was up and down the driveway of the previous owners house. The car had never seen the sand before and I was excited to get it in the dunes. First trip was Halloween weekend. Some of you probably read the trip report, but it was a great trip with @Reece Pettersen in his new race car, my car, and one other car. We clocked some serious miles and I was very impressed with how the car performed. But there was an odd issue, the car popped and sputtered a few times and actually died a few times. I chocked it up to a dirty fuel filter or a dying fuel pump. Checked the fuel filter, of which were perfect, and tested the fuel filter, which was also fine. So I paid closer attention to the issue and noticed the gauges specifically the tach going haywire when the popping was happening. So that led me to believe it was an electrical issue. Voltmeter was pegged at 14 volts so I knew it wasn't a voltage issue. I still replaced both batteries, added a new ground, replaced all power and ground wires, got the alternator tested, and check for any miscellaneous grounding issues. No dice. Went out for the next trip which was Thanksgiving and monitored the issue further to see if I could identify it more. After chatting with the PO he mentioned the car is warm blooded, it MUST be brought to temp before driving it. So this trip I let the car come up to a full 180* and go through at least a full fan cycle before driving it. The issue persisted and I began to notice it would really manifest itself on the first drive after a long pause since the last time it ran. But when the car started up on the second start up (which sometimes took several cranks), seemed to run just fine. So now I'm leaning towards a sensor issue.
When I got home from thanksgiving I replaced the MAP sensor and checked the pins on the computer, as well as replaced plug wires and inspected the harness. Drove it around the neighborhood and it still popped and sputtered. Paid close attention to the fuel pressure regulator and noticed that it was completely losing fuel pressure on startup until all of a sudden the pump would fire back on and the car would start. So I figured it was a crankshaft sensor not sending signal to the computer. Replaced the crankshaft sensor and drove around the neighborhood and it seemed to go away. Bingo, loaded up for New Years very happy. Come first drive of our new years trip and pops, sputters, falls on its face and dies. So back to camp I go to replace the camshaft position sensor, TPS, and IAC. Go for a drive the next day and damn it's stilll doing it. But now the issue has narrowed itself down. The car starts well, idles well, runs up through 1st well, but as soon as you shift into second and give it some juice the car pops a few times and stalls. I can restart it, and off I go for a drive with no issues.
So now I'm almost positive it's a computer issue. And here's my logic:
Fuel Pump Failure? - If the Bosch 044 was failing it would be intermittent, not specific to a time, and would more than likely all together go out. Would not "decide" to run fine after second start up.
Fuel Filters? - Nope, clean as can be
Fuel Delivery? - 60lbs of pressure pinned under load
Sensors? - All replaced
Grounding issue? - new grounds
Lead issue? - New lead wires
Computer power? - Checked, good to go
Spark issues? - New wires and check coil packs. Wouldn't stall a whole motor if just a pack or wire was failing, but would run rough which car does not when running.
So I started calling around to various engine builders to get their 2-cents. Redline was my first call because they did the engine install and harness in 2015. They said I checked everything they would and next thing was to put it on the dyno to check the computer and see if they could figure it out. CBM said the exact same thing. My hesitation with that was spending $1500 on a dyno session just to tell me my MEFI took a dump and I needed to replace it (which I'm now almost positive it is). I had 3 MEFIs fail in my old car and it's safe to say I'm not a fan, and now with the cease of manufacturing of MEFI units, I feel ZERO inclination to ever use one again.
So here's where I'm at now; I've decided to take the plunge and order a Holley Terminator X and do a mid-season rewire. I'll forego a January trip, get this knocked out and send it to dyno first week of February to get it dialed in and finish off the season strong. I was really hoping to kick this bucket into the off season, but it's either I call it a season or get it done. And I ain't done yet, especially if we have Baja in march/april.
My point of the novel: What say you? What haven't I looked at that you guys might? I'd like this passage to be of some help to someone who might experience similar issues in the future.
Some pics if you haven't seen it yet:
When I bought the car, the only driving I had done in it was up and down the driveway of the previous owners house. The car had never seen the sand before and I was excited to get it in the dunes. First trip was Halloween weekend. Some of you probably read the trip report, but it was a great trip with @Reece Pettersen in his new race car, my car, and one other car. We clocked some serious miles and I was very impressed with how the car performed. But there was an odd issue, the car popped and sputtered a few times and actually died a few times. I chocked it up to a dirty fuel filter or a dying fuel pump. Checked the fuel filter, of which were perfect, and tested the fuel filter, which was also fine. So I paid closer attention to the issue and noticed the gauges specifically the tach going haywire when the popping was happening. So that led me to believe it was an electrical issue. Voltmeter was pegged at 14 volts so I knew it wasn't a voltage issue. I still replaced both batteries, added a new ground, replaced all power and ground wires, got the alternator tested, and check for any miscellaneous grounding issues. No dice. Went out for the next trip which was Thanksgiving and monitored the issue further to see if I could identify it more. After chatting with the PO he mentioned the car is warm blooded, it MUST be brought to temp before driving it. So this trip I let the car come up to a full 180* and go through at least a full fan cycle before driving it. The issue persisted and I began to notice it would really manifest itself on the first drive after a long pause since the last time it ran. But when the car started up on the second start up (which sometimes took several cranks), seemed to run just fine. So now I'm leaning towards a sensor issue.
When I got home from thanksgiving I replaced the MAP sensor and checked the pins on the computer, as well as replaced plug wires and inspected the harness. Drove it around the neighborhood and it still popped and sputtered. Paid close attention to the fuel pressure regulator and noticed that it was completely losing fuel pressure on startup until all of a sudden the pump would fire back on and the car would start. So I figured it was a crankshaft sensor not sending signal to the computer. Replaced the crankshaft sensor and drove around the neighborhood and it seemed to go away. Bingo, loaded up for New Years very happy. Come first drive of our new years trip and pops, sputters, falls on its face and dies. So back to camp I go to replace the camshaft position sensor, TPS, and IAC. Go for a drive the next day and damn it's stilll doing it. But now the issue has narrowed itself down. The car starts well, idles well, runs up through 1st well, but as soon as you shift into second and give it some juice the car pops a few times and stalls. I can restart it, and off I go for a drive with no issues.
So now I'm almost positive it's a computer issue. And here's my logic:
Fuel Pump Failure? - If the Bosch 044 was failing it would be intermittent, not specific to a time, and would more than likely all together go out. Would not "decide" to run fine after second start up.
Fuel Filters? - Nope, clean as can be
Fuel Delivery? - 60lbs of pressure pinned under load
Sensors? - All replaced
Grounding issue? - new grounds
Lead issue? - New lead wires
Computer power? - Checked, good to go
Spark issues? - New wires and check coil packs. Wouldn't stall a whole motor if just a pack or wire was failing, but would run rough which car does not when running.
So I started calling around to various engine builders to get their 2-cents. Redline was my first call because they did the engine install and harness in 2015. They said I checked everything they would and next thing was to put it on the dyno to check the computer and see if they could figure it out. CBM said the exact same thing. My hesitation with that was spending $1500 on a dyno session just to tell me my MEFI took a dump and I needed to replace it (which I'm now almost positive it is). I had 3 MEFIs fail in my old car and it's safe to say I'm not a fan, and now with the cease of manufacturing of MEFI units, I feel ZERO inclination to ever use one again.
So here's where I'm at now; I've decided to take the plunge and order a Holley Terminator X and do a mid-season rewire. I'll forego a January trip, get this knocked out and send it to dyno first week of February to get it dialed in and finish off the season strong. I was really hoping to kick this bucket into the off season, but it's either I call it a season or get it done. And I ain't done yet, especially if we have Baja in march/april.
My point of the novel: What say you? What haven't I looked at that you guys might? I'd like this passage to be of some help to someone who might experience similar issues in the future.
Some pics if you haven't seen it yet:
