So I had a parasitic battery drain now car cranks and won't start. and now this P0601 code, what does that mean? Bad ECM/PCM? if so, that is absolutely PATHETIC, already been through 2 or 3 BCM's, so if the ECM is bad too that's wild but it is 27 yrs old now..and yes I'm aware of vats which i have bypassed with a professional built resistor from ebay as i know vats doesn't allow car to crank.. I'm not getting fuel, fuel pump isnt priming and is brand new, only comes on for a split second.. i have owned 4th gen f bodies for 14 years now..kinda over these cars as the interior/ wiring and electronics are basically cheap cavalier/ sunfire economy crap, the windows barely go up and down on these cars when brand new bc the wiring is so thin from the factory, evidently the bcm's aren't much better and the ecm's are only slightly better than that evidently. All these little issues are annoying, I'm in my 30's this stuff is alot more annoying I'm not a teenager with my first car working a part time job with no bills seriously getting tired of the penny ante BS with this car!! The engines however have been great, getting a GMC Sierra was one of the best decisions I EVER made, I like these F bodies, I even swapped 6.0 LQ4 in the place of an original LS1 car because it was high mileage into this '98 which I am speaking of, but I'm so sick of electronic BS and problems on these cars, gauges kinda climb as I am cranking it, doesn't seem normal to me.. just cranking, getting spark but no fuel, 10 psi on fuel rail.. fuel prime doesnt sound normal only primes for half a second.. maybe i should just get a cavalier and ls swap it? 😆 no seriously i dont want to sell the car or pull the almost brand new LQ4 that's only been in there a couple yrs and sell it, because i've done so much work to the suspension, etc.. just a HUGE disappointment..i know these cars are not as hot as they once were it's not 2012 or even 2016 anymore so few people are working on them these days compared to just a few yrs ago as these cars were pretty low in production numbers and even less for the v8 cars.. ton of interest in them 8 or 10 yrs ago, parts like bcm's ecm's are even harder to find now and more expensive because there are less and less parts each year, engine/ driveline parts aren't going anywhere tho.. its all the electronic **** that's a PROBLEM!!..thank God for my Sierra, just insanely bummed.. any ideas? Anyone ever have this issue? What now? Just buy an ecm for a '98 ls1 or have mine refurbished? Or just repin my harness to a '99-02 style which are way cheaper and more readily available.. what to do? Then, what if it still doesn't start? 🤣🤣🤣🤣 this is so stressful 🤮

 

Not surprised, the 98 computers are junk and have been failing left and right for the last 10 years with all sorts of weird unexplainable problems. All of the complaining though... something that is 27+ years old though is going to have problems, maybe you should buy a newer car if it's all too much for you? If you decide to keep the car just repin for a 99+ PCM and go about your day. The gauges spiking when cranking/startup is a known problem on the older gauge clusters with lower voltages as well, it is what it is.

 

Thanks! That's great to know, now i will just have to repin the harness if i go that route. I do have a '99 5.3 truck ecm which i thought would work but I am not sure if it has to be from an actual f body.. but now reading more, if going to the 99+ ecm causes the fuel gauge not to work unless you change out the tank i wouldn't have any interest at all in doing that and i would need to know exactly what's involved in every step if i attempted this, so now I'm on the fence about this, I'm not interested in tuning the car, just want it to run with the factory stuff that it has.. geeeeeesh what a hassle, car continues to sit.. dying.. with all those new parts on it..

 

If you're sick of electronic problems on these cars, definitely don't buy anything new/newish unless you plan to dump it long before it's as old as your current car. New stuff has exponentially more complex electronics to break, and reliability/durability of many new/newish cars has slipped backwards in recent years due to rapid onset of overly complex tech and OEM outsourcing of parts to low quality suppliers. Honestly, I pity anyone who tries to keep a 2025 model on the road when it's 27 years old.

FWIW, my '98 has none of the aforementioned issues, but it's low mileage and original other than some bolt-ons. I've owned at least one LS1 F-body at every given moment for the last 26 years, and I've had my current '98 for 21 years. These are excellent cars when they've been well cared for, mine has held up great, but if your car has a ton of miles and/or has lived a rough life then you really have to expect some stuff to fail at this age.

You mentioned a battery drain and also that an engine swap had been done. The P0601 code can sometimes be tripped by issues relating to the PCM ground path, something which might have been disturbed either during the swap and/or while repairing or diagnosing whatever issue was causing your battery drain.

 

I get what you are saying about the newer cars..but i have a gmc sierra thats not new but newer than this and they don't have all these issues, im speaking of issues like from the factory with the pass window being slow it was a design flaw and it puts more stress/ heat on the solders in the body control module because the small gauge wiring puts more of an amp draw on everything but that's a rant for another day. . I just don't see how it's feasible to buy a 99+ ecm, repin the harness, btw i don't even know what I'm repinning and also i saw where you have to extend wires? All to just still not have a gas gauge and still have to swap the cluster and 99+ fuel tank..all because they are a easier to tune[something i am not going to do] it already has a stout LQ4 in it.. looks like it'd be easier to just get the '98 ecm refurbished... and haa i thought that too..ok, the car was having this problem with the battery drain before I swapped the engine, and i had been unhooking the negative ground from the battery for that reason so my battery wouldn't drain.. just a little backstory, wiring harness was put on correctly during the engine swap and inspected well just for this reason.. everything looked fantastic wiring wise.. i even replaced the ground cable going from the battery to the passenger side of the engine block[near the passenger motor mount] just in case to make sure it was getting a good ground there.. i had paid special attention to the grounds and putting them back as i was hoping i would find the oroblem during the engine swap because at that time, the car was still starting and running fine it just had the parasitic battery drain overnight i kept driving it for another year unhooking the negative battery terminal overnight.. and now this crank, no start situation came up recently..

 

My '98 still has the original power window motors (and they are pretty quick compared to most) and original BCM. The window motors seem to last a lot longer on cars that don't sit outside in the elements. Only one of my four 4th gens ever actually needed window motors, and it was the one that sat outside and always got exposed to the elements, etc. My BCMs have all been fine - but these are also repairable; you can just re-heat the solder joints that are cracked and put it back into service.

FWIW, my Cutlass is 51 years old. This was once the best selling car in America; they weren't junk by any means, they were well built cars. However, even at just 42k miles, I had nearly every problem in the book with mine 3 years ago when I bought it. Every system - other than the engine/trans/axle - had to be gone through and sorted out/rebuilt/replaced. Nearly all the supporting stuff had failed or was failing, or in need of service. This stuff can happen even to the best built cars when they get old.

Seems like I just saw a '98 PCM go up for sale a few weeks ago. They aren't super easy to find, but they are out there. I wouldn't do the '99+ swap for a car that doesn't need extensive tuning (such as a forced induction setup). The '98 unit can be tuned just fine for a basic engine build. Those PCMs do seem to be more prone to failure during the tuning process though.

Thing is, you have some sort of electrical issue causing the drain. This is a wild card issue that may or may not have some bearing on what has happened to the current PCM, it would really suck if this same problem caused issues with a new PCM. You can still investigate the various circuits to track down the drain even if the engine won't start.