Misc undiagnosed engine woes

bengal taiga

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I received a general question from another D-Jetter but I have been unable to respond despite trying several times for several days. So, with the indulgence of other board users, I will take this opportunity to do so here.

"I have a csi. This evening upon start up it ran for a few seconds then nothing. did this two or three times and then I let her sit for about 20 minutes. Went out and started quickly. Took it for a drive. Ran horribly. backfired in second and third upon acceleration. Missed considerably. never had this happen. The caveat, I have been painting some engine parts the last two evenings. Top side of block that is visible, resevoir tank. Could I have pullled a wire during taping that has caused this horrible backfire. Also, when I returned from the drive-reddish fluid under car. "

Unless you have an automatic transmission, with red transmission fluid, OR Dexcool coolant (its red too) I would expect that the red fluid under the car is from your power steering. My pump which can be seen most easily from the bottom front of the car has a tendency to sweat a drop or two. In addition to the steering box and the pump, there is always the possibility that a hose or hose fitting that is loose. Check your reservoir to make sure it has an ample supply

Respecting your more pressing issue, if you have not already corrected your problem, I strongly suspect you have answered your own question. I would guess you inadvertently disconnected something. This is easy to do given that you likely have a wiring harness that has some hidden corrosion or weak wiring.

IGNITION

FIRST- backfire and rough running could be caused by something very minor and not necessarily related to fuel injection. If you loosened a coil wire, a condenser wire, a wire to the ballast resistor, that might easily account for a backfire and poor engine operation. Its almost as though someone someone is turning the ignition key off and on very fast. I can't visualize any ignition wiring you may have disturbed by the coolant reservoir, but part of the wiring harness clearly runs nearby. Recheck the distributor wiring. Pry off and press on all wires near or on the coil and ballast resistor. I am afraid to mention this, but all of the wiring depends upon decent grounds, so I would check all grounds too. If nothing else, it should give you peace of mind, but given the probably age of most wiring, you never know what you are going to find.

FUEL INJECTION

Most of the manuals have a troubleshooting guide that starts with checking the fuel pump. I am not close to any manuals, so I may overlook a few things.

If you can hear it, it pump is probably a-ok. If not, you have a fuse that may be loose or corroded, a relay that may be bad or corroded, or maybe even a bad pump. Since you got your car running. I doubt it is the pump.

Next, I might double check the connection to the injector trigger points at the lower portion of the distributor. I know you didn't mention painting near that area, but I would check it anyway, since a loose connection there can account for your starting a crappy running issues. The area is fairly exposed to vibration, heat and moisture too, so it couldn't hurt.

You have a cold start valve at the top of the manifold in the very middle (driver's side). Double check its connection. Same applies to the temperature sensors at the side of the block with the small hoses. I do not expect they are bad or even loose, but it is possible you pulled one part of the wiring loom and inadvertently loosened what you cannot see.

Since you mentioned working near the coolant reservoir, you could have easily loosened or even caused a break in any of the sensor connections mentioned above on the lower side of the block (drivers side). More directly related are the connections to the pressure sending unit mounted just to the back side and underneath the reservoir. If you are unfamiliar with it, it is baseball sized and you can easily trace it by following the vacuum hose from the manifold that feeds it. It could be that you disconnected the vacuum hose itself, since it is a press-fit connection.

Summary:

This is an off the cuff guide. Given your message, I would assume you likely disconnected something which you already discovered and resolved. Nevertheless, if you are still on the proverbial side of the road, you could have more complicated issues that show up without warning. You need 30 lbs./in2 of fuel pressure to have your system function properly. If you have a fuel pressure regulator that is bad, you will have to adjust it or replace it. They are available and other regulators from other models can be adapted for use on the E9. This might account for your symptoms. Just as simple a reason for your symptoms might be a bad pressure sending unit. If you suck on the vacuum port to this unit and it won't hold a vacuum. There's nothing to do but replace it. Its an easy proposition, but for the fact that they have become rare, hence my own posts. I hope these are not your problem, or if they are, you have someone nearby who keeps extra parts under their pillow!

Very good luck!
 
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