Hello all,

Long time lurker here who finally broke down and joined. Great info in all of the articles and threads which has supported me to this point, but now I am stumped!

I keep getting EGR codes (54 and 55, if I remember correctly, I know they are EGR codes, might be 53 and 54), although not causing any issues and they quickly go away, I just ran into a severe problem. Left on a 5 hour drive and 2 hours into it, car started missing like a mother. I immediately pulled off the road and hit the closest Advanced Auto for a set fo fresh plugs (more on my reasoning in a bit). Pulled out the NGK'* for a set of stock AC Delco'*. Car fired up and chirped the tires in their lot..... SWEET! NOT! As soon as I was back on the road, the miss/stumbling came back with a vengeance. Long story short, I gave up and grabbed a rental and left my ride with a group of good old boys at a Firestone shop. They couldn;t find anything wrong with it the next day and I had them drive it like mad. Been there two days now and they are using it as their courtesy car, running like a top. They suspect a carbon buildup/EGR failure that corrected itself (the EGR and harness have been replaced within the last 3 months). I tend to think they are right for the following reason:

When I replaced the SC, I also replaced the FPR and injectors. Attempting to be thrifty, I purchased a set of Accel injectors with a #30 flow rate (found this spec in these threads). Immediately after, the car cranks hard to start most of the time, not always, but a lot. I checked with both Accel and Summit and they claim the flow rate spec should be #21. I am a little uncertain of which is which, wondering if they might have a different trim spec listed for the SSEi. Anyway, car does seem to run a little rich on startup (I know the PCM will make every attempt to correct and meter flow rate, but how much can it do)? Plugs did not seem to be fouled. I have a new set of #23 inlectors on the way. If not, I still have the stock set that I can have rebuilt.

Anybody know the correct flow rate for my year and trim? If the injectors are too big, will it contribute to carbon buildup and foul the EGR?

On a secondary note, I found TOMCO'* website and they have some very interesting parts for EGR'*. They make a very nice screened gasket for the linear EGR'*, but not for my year. I did contact them and asked for a solution ( although I think this might be treating a sympton and not the cause). The engineer wants me to mic the inside diameter of the EGR inlet tube and he will send me a basket (screen) to insert and test. If it works, they may put it into production (I guess there is not enough room for them to make a screened gasket for the digital EGR'*. Appanrently their screens almost eliminate EGR fouling, but I am thinking that the maintenance would them be moved to the screen and not the valve itself.

Anybody happen to already know the spec for the insdie diameter of the EGR inlet pipe?

Thanks for all of your help to date!!!

You have 30# injectors stock and a digital EGR. I don't know the pipe ID.

Clean your EGR valve, and lightly oil the solonoid shafts and springs. Check for a coil failing from heat.

EGR cleaning coming this weekend.

Any easy way to check for a coil failing from heat or should I just replace them one at a time with my stock coils?

jwik - thanks for the injector flow rate, any reference material that I can research? I can;t find a spec anywhere.

Is the screen/basket a good idea or am I on a wild goose chase with this idea (thinking of preventing future maint)?

When I get home, I can post before and after results from when I got my stock injectors rebuilt and cleaned. Also PM DrJay about them.

Thx jw,

I PM'd DRJAY.

Looking forward to seeing your results, have a feeling that I will be doing the same. I found a local guy that can do my stock injectors.

Heya, interesting problem. This stumbling problem, is it only when cruising? Does it go away at WOT? How is the idle?

The first thing I'd do is what has already been suggested, pull and clean the egr. You can test them with a 9v battery, here'* how:

http://wellsmfgcorp.com/counterpoint...erpoint3_4.pdf

Its a pretty quick and easy procedure.

You were correct in your original injector purchase, stock 93 ssei injectors are 30#. Do not install the 23# injectors or you will run lean and possibly cause engine failure. The flow rate on the naturally aspirated of your year is 21#.

If cleaning the EGR does not help try replacing your coils with the stock ones and/or check their resistance. If that doesn't work we can go from there.

Hope all goes well.

The car ran great for the first 3 hours of the drive, then started missing as cruise speed, slightly at first, then became aggressive. After I changed the plugs, all was good, for about 60 seconds, then all hell broke loose. At idle speeds, ran fine, accelerate the tiniest bit, choked like mad. Could not get to WOT. Finally, when I coudln;t drive any more and called for a tow, it struggled to rev in park. It sat overnight at the garage and started fine the next day. They have driven the car all day yesterday and today without any issues. Headed back to pick it up tomorrow, then a 45 min drive to stop for the night. Have a 2 hr drive to get home late Friday morning so I might have a good chance for another failure then. I'll do all of your reccomendations this Sat and let you know. I am begining to suspect a visit from the intermittent gremlin, which is always such a nice party. Also, I think I am going to drop off my original injectors and have them rebuilt. If the Accel 30# are correct, my car doesn;t seem to like them all that well (I am saying this due to the extended carnking that happens on startup a lot - 3,4,sometimes 5 cranks before firing as opposed to almost immediate in the past). In any event, the EGR and coils are coming first before I get too far ahead of myself.

Here'* partial results of my reconditioned injectors:

Well I haven't made it home yet to do any of the suggested troubleshooting (great info BTW, thanks to all), but I did pick up the car this morning. After about 45 minutes at highway speeds (70 - 90) with no failure, I took my exit and stopped at a light. When the light changed, I got a little heavy on the foot and guess what ..... several misses. Let the load off and it ran fine. Good thing I was already at my destination. Did some more research and starting to sound a lot like a heat failure of one of the MSD 8224'* (I might have to go to Oregon and buy Will a beer, I know, just shut up and fix it). Hoping I can stretch it out for the 2 hr drive home tomorrow. Still throwing EGR code 55, but I am betting a thorough cleaning will fix that right up. Looking forward to Saturday for some hands on.

About the EGR screen, anybody think that this is worth investigating? I am more than happy to try it, just wondering if you guys think it would be worthwhile?