Starting a sitting truck? Help!

[abbygeiger]

Hello! I have recently started working on a 1994 Ford Ranger. I know it has been sitting for a while, likely upwards of four years, but no way to truly determine. As of right now it is a crank-no-start engine. Prefacing this by saying this is not only my first pre-OBDII car I have worked on, but also the first American car I have done anything other than oil and brake pads to. I come primarily from the Euro scene, and feeling a little bit out of my league with this truck.

It has the 4.0 v6, automatic transmission, and just about 230k miles. I have done all the recommended services for sitting cars, as well as replacing parts I proved to be faulty:

- changed the oil and coolant (oil looked fine, just dirty. no sparkles or milkshake)
- new oil, air, and fuel filter(s)
- drained fuel tank and replaced with new gas
- new battery
- replaced spark plugs (even tested to make sure they were all sparking, and yep they were)
- new ignition coil module
- new fuel pump
- new starter

fuel pressure is fine - checked with a gauge kit
When I drained the gas tank, I pulled about ten gallons of liquid out. There was obvious separation of fluids, I am thinking water got into the tank over time. There was about a 50/50 ratio of fuel to water.

The truck cranks but won't fire up, not even with starting fluid. It is acting like it wants to start, but then sputters and dies out.

Another weird issue is with the fuel gauge itself. The needle gets stuck right in the middle. I found something about an anti-slosh module(?) in the dashboard, discovered a way to bypass it, now the needle moves between showing half a tank and empty. I find this to be weird considering I just replaced the fuel pump, and unless the dash gauge itself is bad, I don't know what that problem is either. Have never seen anything like it.

In a similar post I made on r/fordranger someone suggested I perform a compression test and here are the results of that:
1 - 125 psi
2 - 110 psi
3 - 145 psi
4 - 110 psi
5 - 110 psi
6 - 85 psi

Due to the extreme variances in cylinder compression, I am suspecting a blown head gasket, but have no way of verifying that claim. I have the tools to do a standard block test, but with the engine not actually firing... just would be unlikely to detect any exhaust gases until the truck can at least idle.

I also have pulled the codes from the OBDI and they are as follows:
118 - engine coolant temperature system above maximum voltage / 0 to -40 F indicated
159 - MAF sensor fault, above or below normal
327 - EGR valve position circuit below minimum voltage
341 - the manual that came with my scanner said this code is only for cars, but indicated the octane adjust service pin open
565 - canister purge solenoid circuit fault
566 - 3-4 shift solenoid circuit failure
558 - EGR valve regulator solenoid circuit fault

The EGR codes are especially interesting to me, and thinking I need to either replace the EGR or the crankshaft position sensor as something electronic is clearly not communicating properly. Would a faulty EGR or MAF sensor cause a no-start? What should I look for?

Being a sitting car, I have found a good amount of wasp nests and evidence of other creatures turning the engine bay into a temporary home of sorts. I am currently working up the courage to go through the full electrical system to see if any of those friends chomped their way through some wires. There is also an aftermarket stereo that was installed by the previous owner, had the dash out a couple weeks ago... they definitely did not know what they were doing with it all. Where do I even begin??

My primary goal is to just get the truck to fire up, I can fix the other odds and ends later on.
Should I replace the crankshaft sensor and/or the EGR valve? What else should I troubleshoot or look for? Happy to respond to anyone with more information, thank you for your time!

 

[dvdswan]

Welcome to the site.

Codes can cascade with 1 or 2 more codes, but with that many you might have several issues. Being the 1st code is a bad temp sender signal, my swag would be the ECM thinks the engine is too hot and won't allow it to start. I would start with that diagnostic and run down the line to verify the rest.

 

[alwaysFlOoReD]

Those are not good compression ratios. Did you squirt about a teaspoon of oil in each cylinder to see if compression came up significantly? If they came up then the rings are bad.
If you have access to a leakdown tester then you can narrow down possibilities quickly.

 

[rhekman]

A bad EGR sensor should not cause a no-start. A bad MAF or ECT sensor could cause a no-start, usually from flooding, but the computer still has base maps that should start the engine (and run poorly) in comfortable weather.

However if you're not getting a brief start with starting fluid that would indicate more issues.

As alwaysFlOoReD stated, those are not great compression numbers, particularly the 85psi, but none are zero, and should not cause a no-start.

I would start with the following:
1. Check ignition timing with a timing light while cranking. If you get a successful pulse somewhere in the 8-10° before TDC range the crank position sensor is probably OK.
2. Backprobe the ECT with the key on, you should get a value somewhere between .8 and 4 volts. Less than .5 then the sensor is likely faulty. Also backprobe the ECT signal pin at the PCM (light green/red wire on pin 7 if my homework is correct) to rule out bad wiring.
3. Check the MAF sensor connector for loose pins, and backprobe the connection, looking for between .2 and .7 volts. Code 159 says the computer is seeing more than that during KOEO self test.
4. Visually inspect the engine wiring harness for broken, chewed, chafed wires. If critters have been wreaking havoc, that could definitely cause a no-start.
5. Check chassis grounds.

Good Luck!