Unfortunately, there is not really a way to check for injector clogs without putting them on a bench. The resistance means your coils inside the injectors arent shorted. Doesnt give you a complete picture at all. Im too lazy to check inside the tank but Id definitely replace the fuel filter. One thing you can check is whether the injectors are leaking by putting a pressure gauge on and letting it sit for an hour or so.. you should not see much of a drop in pressure. But really that is just academic as I would send them in to be tested and cleaned. Not required though.. if they pass the leak test you could run them and hope you have good patterns and equal flow. You could scan the banks and see if one side is compensating too much (can do this on the lt1, not sure about yours).

It does look like rust to me as well.. and it looks like the regulator is pretty rusty.. so some came from there undoubtedly.

I would think if you re-installed the injectors you could test at that point.. as long as its closed you are good to test once you replace the regulator. It looks to me like you found the main problem.. if your injectors were replaced recently Id maybe go for it. depends how long it took to put on those 5k miles. If I were on a budget Id probably go for it unless I was concerned about every drop of performance. But do the filter at least and maybe take a peek at the fuel pickup.. as I understand it, its not too hard to get to on the c4. Its possible I suppose the lines are rusted.. at some point you had water infiltration, maybe condensation.. this is why people recommend storing with a full tank of gas.

good luck

 

I haven't decided about the injectors yet, going to check the tank and fuel pump at the back. Also
want to clear our the fuel lines from front to back. By the end of all this I will know a lot more about
my Vette than I did. I bought the car expecting to do some work on it, however after paying close
to $3k a couple years for some work I got spoiled. The car had been dead reliable, karma is catching
up to me.

 

For those interested here's the latest, I have purchased a fiber optic camera ($8 after my points with Amazon) and
it looks like the bottom of the tank is nasty. Now I need to clean the tank, I am going to try to accomplish this
without removing the tank, I am sure the preferred method is to remove the tank but my buddy who has been helping
me is tied up at work for weeks, his company makes medical masks and as you can imagine with the corona virus
scare they are increasing production a lot. I have pumped the gas out of the tank, luckily it was almost empty
already, I have a plan to drain and flush the tank that I will accomplish in the next week. My goal is still
to have this running by April so my son can drive it to his senior prom.

Chuck

 

can you send the link to the camera you bought please?

Ive not heard of amazon points, I'll check into that.. if I was in that program Id probably have around 1 million points by now.

 

The camera was $33, minus the $5 coupon on the order page and then the points I gained using my Amazon card.

 

Nice.. may order one up since you are apparently happy with it. thanks, Ive always wanted one of these. If/when I do my spark plugs Id love to have a look at the cylinder walls before I go spending time and money on a cam for example.

I wonder why your tank is full of crud.. maybe as simple as a batch of bad gas. I had this happen on a diesel truck I used to own. Literally saw them out changing the filters while fuelling and sure enough, 4 filters later it was clean enough to run over 30 minutes. Luckily it was fitted with a spin on fuel filter.. albeit expensive.

 

Find someone with a skinny arm. Siphon as much gas as you can out, then blot out the rest with a rag. Then wipe away all the crud from the bottom of the tank. The opening from the top is JUST big enough to do this. Especially is someone with skinny arms does it.

 

May want to use a piece of 'Scotchbrite' and some acetone.

 

I am finally trying to get my car back on the road, due to personal reasons I had to delay
fixing my car, and I am having the hardest time finding a couple items. I need the EGR vacuum
harness and the PCV & crankcase ventilation hose for my 1990 C4 L98. I even went to the local
Chevrolet dealer and they were unable to order the parts. I have seen one EGR vacuum harness
on Ebay for $149 (new), that seems high but if I have to pay it I will. Anyone know a place that
sells these items?

Thanks,
Chuck

 

Check with Mirrock Corvette https://mirrockcorvette.com/

 

There are some placed that specialize in Used Corvette Parts - check with Vette2Vette or just Google Used C4 Corvette Parts.

 

Thanks, I'll take a look!

 

Thanks, I'll take a look. Trust me when I say I have been on Google constantly.

 

There are some PCV hoses on ebay right now. However, when I did the intake on my 1990 the PCV hoses broke in a couple places. I used some electrical tape and did a nice wrap, 2 or 3 layers. Turned out nice. It's been a few thousand miles and no problem so far.

 

The bottom picture is showing the hose from the crankcase ventilation on the driver's side
valve cover? I did actually tape the hose/pipe back together on the passenger side, since
it is turning into an issue obtaining the new hose I may just use it.

 

Remember - this is get the car back on the road - not a concours judged event. Worst case - get some tube with an appropriately sized ID, and using a Tube Bender - bend it to something approximating the OEM piece - then use a couple of pieces of rubber hose to connect the line to the manifold and the PCV Valve. A couple of Clamps - and you're back in Business.

 

No doubt, but for right now I am paying someone to fix it and would prefer to have
the correct hoses.Though I may have to run to Harbor Freight and pick up a Tube Bender
for use later, always looking for an excuse to buy new tools....

 

Yes.

 

After all that..
the evap canister purge valve can stick open and give you the biggest vacuum leak,
its under the left headlight.
on my car it has a plastic domed cover. Held on by a 10mm bolt.
could be part of the “overnight “ problem.

 

I thought I would provide the final fix for the car, I needed new head gaskets.


After replacing the fuel pump, filter, fuel pressure regulator and fuel injectors it still wouldn't
run so I took it to a shop. The shop got the car running but it was pushing oil out of the dip stick,
milky oil. We all know what that means and once replaced the head gaskets it runs great and the idle
is much smoother. The only issue I have now is after driving it for ten minutes, on multiple
short trips all the warning lights start flashing, including the speedometer screen. Then the
warning lights, speedometer screen and dash lights go out. Once I let the car cool off everything
works until the next drive longer than ten minutes. The other gauges still work (oil temp,
oil pressure gauge, coolant temp and voltmeter). The tachometer does not work and has
not worked since I purchased the car. I am assuming this is a ground or possibly a cold
solder joint. I have the FSM and will finish troubleshooting once the cast is off my recently
broken right wrist. Be careful walking on ice..........

Chuck