Troubleshooting + New stuff

Troubleshooting

The 350is runs on a Cobra (X3Z) ECU. While it "runs" and "drives", there is a huge hesitation starting around ~3200ish rpm under WOT. It only revs cleaning to the limited under light throttle application. With a Cobra MAF and 24lb injectors, there shouldn't be too many issues using this ECU . . . supposedly. To avoid shotgunning parts, I checked all the usual stuff  (no codes other than the missing emissions equipment) and came up with some possible issues:

• Questionable grounds
• Vacuum Leaks
• Dirty MAF
  
• Fuel
• Old fuel
• Old ass fuel pump
•  Ignition
• Spark Plug Gap
• Distributor issues
• Suspect Coil
  
• Suspect O2 sensors
  
• Suspect ECU

There are some free and near free (both labor and $$$$) items. The basic stuff like checking grounds, cleaning the MAF, spark plug gap would be a great place to start. If those do not resolve the issue, I'll move on to replacing part that I currently have on the shelf. An example is the fuel pump and strainer are factory original 1993 items. I'll replace this due to its age. If that fails, then I'll move onto other parts.

New Stuff 

The EEC-IV is capable of running a lightly modified 5.0L. Unfortunately, all these ECUs are old, used units that are highly suspect. They may have solder issues or have been incorrectly modified. A fragged ECU was one of the initial problems that plagued this build.

 

A canned tune cost $250 with the price rapidly increasing for true dyno tune. The equipment to self tune an EEC-IV is $300-650, but I would still be stuck with the EEC-IV. If the current X3Z is fragged, I would have to find a decent replacement to use. Those replacements vary from $30-500. So what to do? Enter MicroSquirt!!

 

I picked up this little box and adapter for cheap. As usual, it is from an abandoned project. Even with adding in the cost of wideband (needed for any type of tuning) and a fully unlocked suite of tuning tools, it is about the same as decent tune.

Before I install this, I'll make sure the car is mechanically sound and running as best as it can with the Cobra ECU.

Gimme Fuel Gimme Fire

 I received my refurbed sending unit

It looks way better than the one that came out of the 780.

Checked all the hoses for rot and they "looked" ok. After stabbing in the refurbed unit, I hotwired the pump to prime the system and sprung a giant leak. Sigh . . .

The pressure hose that "looked" ok apparently was not ok. It ruptured in 3 . . . THREE . . . places. And of course the hose clamp is completely out of view and can only be accessed by dropping the tank.

Well, jacking up the car on soft dirt was not happening. Out comes the razor to trim away as much as the hose as possible. I took a pair of side cutters and snipped the hose clamp. Success!!

Eh . . . not so fast. I have to get a new clamp on there and tighten it blind. After what seemed like hours of fiddling, I had the new hose and hose clamp on it. Let's try this again . . . .

I hotwired the pump to prime the system and found no leaks.


She's running a bit rough and coughs a bit; not bad for sitting up for 3 years. After idling for about 15mins, it did smooth out a bit, but still has a slight hesitation. Took her for spin around the yard with the rear suspension riding on the bump stops (nivomats are dead). A tune up will probably make her sing. For now, it runs and it drives.

-=PJ

Fuel, Varnish, and Tar?

I put some hands on the Volvo 780 today to replace a dead fuel pump.

It's your standard, late 80s 2 pump setup; one internal and one external. The external pump was dead. I hooked up my siphoning contraption to pull all the old ass varnish . . . I mean . . . fuel. After jacking the car up via the approved jack points and using jackstands, I attempted to remove the external fuel pump assembly. Every inch of the underbody was covered in this tar like goo. I guess it could be worse . . . I mean there is rust on the top and none underneath

Anyway, I removed the crapped out fuel pump and old fuel filter and reinstalled everything. With a fresh battery and three gallons of fresh gas, I turned the key and the pump spun up! I cycled the key a few times and check the for leaks. No leaks found and internal pump spun up during the cycling to prime the system. YAY!! Turn the key and the 780 sputter to life . . . WOOOWHOOO! Wait . . . Wait . . . why are you coughing? Why are shutting down? Sigh . . .

Ok, let's check the normal stuff . . . Still no leaks. External Pump still cycles . . . albeit slowly??? Fuses are good. Relays are still clicking. Why hasn't the fuel gauge moved? Hmmmm . . .

I ran a test on the internal fuel pump and nothing. Great.

So after stuffing myself in the trunk to pull the fuel sending unit, I emerged with this:

Well f**k. None of that looks good and it is missing a fuel strainer. Great. I couldn't find it in tank. Awesome! That would explain what stuffed up the pump. Sigh . . . Let's see how much this is.

780 1988–1991 Fuel Pump Assembly with Fuel Level Sending Unit

3507499

$545.45

Hell to the nizzy!

Searching . . . Searching . . . Searching . . . Searching . . .

The local Pull-A-Part has a few Volvos on the yard with the same fuel sender and pump combo for less than 30bux. Add a $25 pump, $5 strainer, and $5ish in wiring kit . . . I could do this for ~$70 with shipping included.

I found a Volvo parts recycler on eBay that has a few of these for $180. Yea . . . it's more expensive but it comes with a new pump and strainer ready to dropped in. And I don't have to curl myself into a ball in musty ass trunk for an hour dealing with crusty clamps and wasps to remove a highly suspect unit.

Well . . . you know my time is something I can't make! Time to order.

-=PJ

Depowered Roach

Well what's next for the Roach?

I just can't leave well enough alone :)

-=PJ

And Now THIS!

We put in a little work this weekend.

Such a handsome, classic face!

Oh . . . what is this?

The 350is has not seen sunlight since 2014.

She's low!

She runs and drives!

Holy crap . . . She runs AND drives!! I took her down the road and even with a stock tune . . . coughing and spitting long the way . . . the torque off idle is intoxicating. I did a small burnout just pulling up the driveway.

So what's next?

The power steering needs some attention. It's sorta there and sorta not. Other than the tune and tach, the rest are are easy breezy stuff. We'll use sheet metal or ABS plastic to get those done.

-=PJ

Huge Updated on 350is

We've been putting in some time on the 350is. Enjoy the photos . . .

Interior wiring clean-up:

Fan/Radiator Shroud:

Clutch Slave Cylinder and Bracket:

Engine bay Wiring Clean-up:

Exhaust:

The Office:

Almost done!!

My welding helmet died and it started raining. We just need to finish some incomplete welds on the exhaust, sand it down, slap on exhaust paint, and reinstall. After that, one final check before a test drive!

-=PJ

We've been busy

We put in some work in late 2019 and the start of 2020. Let's keep the momentum going!

BMW 350is


BMW 530i


Dodge Dakota


The Roach (Corolla)

-=PJ