code 21 but runs fine! wtf! help!

[compactfean]

I have a 89 240 with a redtop, ton of nods.I get code 21 @ random but can't fund a guide to fix it. I have never thrown code 11 so that rule out cas. Does anyone know how to diagnos this? The wire in the back of the coil harness supose to be grounded or not? Car cuts out a little at around 6k but I don't think its ign. Related.(740 injectors with stock fuel pump)

[compactfean]

Someone shine a little light here?

[zach-Ka]

You need a better fuel pump. A stock sr will cut out in higher rpms with the stock pump.There is a wire off the coil harness that does need to be grounded. Stock position is the back of the head. I soldered the grounds to a thicker wire and grounded it to the fire wall though.

[compactfean]

Yeah I figured that was my high rpm issue. Ive got a walboro on the way. What's the most boost/horsepower you ever heard running pumpgas? (91 octane here) ill check my ground and see if thats my code21 issue.

[zach-Ka]

Well the stock turbo can only handle 14 psi. But the was a guy in the sr forums using pump gas at 19psi on a fairly large turbo. and he made I think 342whp with stock internals with the exception of cams I believe.

[compactfean]

I'm running gt3071r 270 tomei cams and 740 inj sleeved block 9:1 pistons rods solid lifters etc.its pretty much bullet proof. I'm only running 10lbs until I upgrade my pump and fpr. I wad just wondering what I can pull with my setup without spending the money on race gas every tank. Anyone with dyno experience got any info? Oh and that wire was grounded very well. Anyone have anymore ideas on code 21?

[compactfean]

New problem! So now my car is loosing cylinders at random. Ill turn the car off and restart it and runs fine for a little bit and then I start to loose cylinders again. I'm almost positive it is spark but can't Tell because everytime I park the car after the problem the car runs fine. Can someone please tell me how to test the ignitor chip? I thing its going bad and have searched on how to test but can't find anything.

[l3thalyendl3ss]

Okay get a electrical lead tester and check continuity from one side to the other see if you get a tone at all the connections from both sides. (the ignitor chip of course).

[compactfean]

A tone? I have a tester what exactly am I looking for? Is there a certain resistance number I'm shooting for? Thanks.

[compactfean]

Okay so ive checked continuity between all the pins and nothing. I'm not sure if I'm checking the right pins though. Ive got 5 in and 4 out. And if I have no continuity how does my car still start? Am I supposed to check continuity between certain pins?

[compactfean]

Well I can't get the problem to reoccur and am still throwing code 21. I have talked to two Berry reputable mechanics and both said ecu so I'm going to post a new thread if problem reoccurs. ....end of thread for now.

[compactfean]

I fixed it! So for any of you with code 21 fallow the fsm to the t! What I found is that there are two blue and red wires when you do the wiring by the fuse box. Frsport says to splice blue and red to black and red. What they don't tell you is that the small b/r is power to ignitor chip. The large b/r is the power wire to the coils so you Need to splice both of them!