OK fellas some of you know I've had a drawn out rough idle and power loss problem ('90 IROC 350 TPI, 40K miles) for which I've done almost everything to fix. Anyways, got out the stethoscope today and all injectors are clicking, no excess noise from valvetrain through stethoscope, and good vacuum readings (20in. Hg at idle, erratic by + - 1in.Hg). So I disconnected the injectors one at a time and only about three of them made the idle slow down significantly, while the others just made the engine shake more than it already does. Is that normal? I don't think so, but I'm not sure. The entire ignition system has been rebuilt, so I'm thinking new injectors.

What are the odds of this on a car with so few miles? I would send them to Rich, but I need the car and can only afford it down for about two days, and he told me the Multec injectors aren't much good anyway. So, if you guys think it is the injectors, should I buy the new Accel ones or the 24# SVO and an AFPR? The car is essentially stock. How long will it take me? Thanks guys.

 

Jethro,

In the words of our favorite former Chief Executive, "I feel you pain..."

My '86 TPI stated having the same symptoms at 22,000 miles. I fought the problem with distributor caps and rotors, wires, plugs, coils, pickups, reluctors, PROMs, valve adjustments, fuel fitlers, regulators, etcetera for two seasons before I could no longer avoid the inevitable. My injectors were suffering from poor spray patterns and flows. Two of mine were off flow rates by more than 15%, and would only make the idle change a little when unplugged. I built a "cheater" that would allow me to power the injectors individually for testing. If I applied a constant voltage to the suspect injectors, the idle would improve, but I couldn;t operate that way except for testing.

After removing the injectors and sending them to Cruzin' Performance, my problems were solved. Unfortunately, the service takes about two days, not including the shipping time. It would be nice if some day they would accumulate a supply of spare injectors and offer an exchange service. The risk there is that they would be shipped a set of completely dead injectors as cores. I guess an exchange would have to cost a little more to hedge against getting shafted like that, or require a hefty core deposit that would be refundable. Until then, you'll have to wait for about four days if you use next-day shipping of opt for new injectors at a much higher cost.

I wish I had a different solution. There is a possibility of getting a spare set of injectors on eBay and sending them in for service, but then the cost might be prohibitive.

The SVO injectors are a pretty good deal compared to stock GM prices, and should feed your engine without a problem. The whole job might take you one long day (8-12 hours) if you have all the parts at hand and don't encounter too many tough fasteners.

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Later,
Vader
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"I'm'a do Things My Way - It's My way or the Highway."
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[This message has been edited by Vader (edited March 11, 2001).]

 

Thanks a bunch, Vader. I've been denying that it's the injectors for quite some time myself, but there is so little left to do with the car that I have to face the music. Should I run the 19# SVOs and bump up the pressure, since the 24# may make me run too rich? Looks like I'm in for some fun next week .

 

Jethro,

Here are some options:

http://cgi.ebay.com/ebaymotors/aw-cg...ndexURL=0&rd=1

http://cgi.ebay.com/ebaymotors/aw-cg...item=568440041

I'm thinking hard about that LT1 setup myself.

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Later,
Vader
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"I'm'a do Things My Way - It's My way or the Highway."
Adobe Acrobat Reader

 

Thanks, Vader, that LT1 setup does look pretty sweet! I'll probably just stick to replacing the injectors only, though, so the wife won't kill me over spending too much .