Idle / Lean running - 87 Head Scratcher

[scarceller]

Are those stock injector?
Glad you found the problem, I suggest also doing a fuel delivery rate test to be certain nothing else got clogged in the fuel system.
Easy to do the test.
- Engine Off
- Put a hose on the fuel pressure test port and route it into a clean 1 gallon catch can, I like a clear milk container for this.
- Be sure battery is fully charged
- Jumper power to the fuel pump fuse directly from battery
- Run pump for exactly 1 minute
- You need to have more than 1/2 gal in 60 seconds to be in spec

A healthy 3.2 fuel system usually delivers 3/4 to 1 gal in 60 seconds but spec is min of 1/2 gallon.

[almostordinary]

No not stock injectors, also less than a year old.

Haven't heard of this test, but it's free!

I'll give it a try this week and report back.

Thank you!

[scarceller]

What injectors are you running? Do you have the Bosch part number? just curious.

Originally Posted by almostordinary

No not stock injectors, also less than a year old.

Haven't heard of this test, but it's free!

I'll give it a try this week and report back.

Thank you!

[almostordinary]

I'm actually running these which have been phenomenal

https://www.ebay.com/itm/372467329781

[scarceller]

I think you mentioned you have a WBO2 gauge, if so disconnect the stock O2 so it runs open-loop.

Then one of the best testcases to determine overall mixture is to run fully warm on level road in 4th gear 3000RPM steady state. Your AFR should be in the 14.4 to 14.8 range if everything is correct.

That's steady state part throttle AFR test that I've come up with and it's extremely accurate AFR test.

[scarceller]

These are 24lb low impedance injectors, that's in the correct ballpark as the stock ones.
Nice find.

Originally Posted by almostordinary

I'm actually running these which have been phenomenal

https://www.ebay.com/itm/372467329781

[almostordinary]

Wanted to close this thread out.

I found the ultimate issue.

I had a set of new BEHR ignition wires on since I installed the motor.

Turns out some of the connectors were loose (to the point of disrepair) , and some were letting water into the boots (Had green crud).

I bought new Clewett Engineering High Performance Spark Plug Wire Set, 8mm, BLACK from Pelican... and she holds 14.7 AFR steady... zero shudder...

I just completed a round trip drive from LA > Victoria BC and back... absolutely zero issues.

[wazzz]

Thanks for the feedback. BERU (not BEHR) ignition wires have had quality issues lately.

Regarding your new Lucas injectors, there is also this set from the same vendor, same price, even a little cheaper, and they are specifically said to be for our 3.2 engines. Plus the six injectors in the set are also flow matched. Cannot be bad.

Edit: if link above is not working, the simple and correct version for it is www. ebay. com/itm/372106959677 (remove spaces)

[almostordinary]

Ahh BERU... thanks for the link.

Hopefully someone having a similar issue can toss those out of the equation. The Clewett wires are top notch and the sleeves on the distributor end are well sealed to keep water out... a lot better quality than the expensive stock wires