Stalling problem

BJPZ28 · 04-09-2007, 11:45 AM

94 z28. I just put in a new fuel pump, after having a hard starting problem. Just before I changed it, it had stalled on me when taking a slow turn. So I figured the pump caused that problem to, But it has stalled on me twice more. It starts after sitting for a minute or so. No SES, no high temp. Did the OPTI and waterpump last year. Is it poss that there is air in the cooling system causing this. I pulled the vacuum line of the FPR and it was dry as a bone. Any advice?

mrmint69 · 04-09-2007, 05:13 PM

I have seen lots of people on here have there optis come loose and cause the problem your describing. I think you could check it if its tight on there. One guy went over a bump and it caused it to come loose enough the car died. Maybe the dying during turning is a sign something is coming loose. I have the samething but mine only dies during idle so i am curious why this happens so much. I am just guessing but it seems like after the optis are replaced within 6 months to a year is when the thing loosens enough to cause problems.

BJPZ28 · 04-10-2007, 04:53 PM

I'll have to check to see if it broke loose. Drove it all day yesterday,took it to work today. Went to the store after (about 2 miles away) When I went to leave, I started it and it stalled right away and I couldn't get it started for a 1/2 hr. Called AAA in, towed it home and it fired right up! WTF! Wouldn't it sputter and miss if it was the OPTI again. Anything else?

BJPZ28 · 04-10-2007, 04:58 PM

It has smelled like it's been running rich for a while. Don't know if thats a clue. It has a msd coil and a K&N filter. No other mods at all.

BJPZ28 · 04-11-2007, 05:45 PM

Could it be the ICM? Got a fuel pressure gauge on it waiting for it to happen again.

Z28LT1_Just_Nasty · 04-11-2007, 07:59 PM

Does it backfire at all? Stalling can have so many causes. Could be a loose battery connection, bad opti/coil, etc.

I know once for example I stalled out a few times and it turned out the battery connections just got a little loose.

BJPZ28 · 04-11-2007, 08:34 PM

No sputtering, no backfire, no hesitation, battery connections fine. New msd coil last year(could stick the stock one back) It cranks over fine, no power(elec) loss. Started it when I got home today, let it run, ran inside for a minute, came out and it had stalled. I cranked it and nothing. So I put the pressure gauge on to see if there was a drop, and it fired right up. Just finished messing with it and I can't get it to stall while I have the gauge on it. I would think the opti would have shown some obvious signs. This was such a reliable car untill I started parking it for the winters and rainy days.

MyWifesZ28 · 04-11-2007, 09:18 PM

How about the fuel filter?

blitzer454 · 04-11-2007, 09:42 PM

Possibly a bad ignition switch. When you take a turn the keys hanging from the key chain cause the key to wiggle around in the ignition switch causing an intermittent bad connection. Just a guess.

BJPZ28 · 04-12-2007, 04:44 AM

Gonna do the filter. That cheap. It only stalled once when turning. Yesterday it stalled just idling in the garage. The biggest problem is getting it to stall when I want it to so I can check some of the things you guys are suggesting.

BJPZ28 · 04-12-2007, 05:37 PM

Finally got it to stall with the fuel pressure gauge on. There was no drop at all. I'm tempted to pick up an ICM, but that's a $80 guess. I hope it's not the OPTI again. Since I've been messing with it at home, it has only stalled twice, 10 minutes after a cold start each time. Starts after a minute or so, I turn it on and off again and again, let it run for 1/2 hour, on, off...... Gonna try it again tonight once it cools totally to see if thats consistant.

BJPZ28 · 04-13-2007, 06:00 PM

Again, stalled after 10 minutes from cold start. But started before I could check anything else. Help! Any suggestions?

blitzer454 · 04-13-2007, 07:45 PM

Kind of sounds like a bad optispark that has become heat sensitive. I know from experience that the engine will just die out of the blue and not throw a code when my optispark malfunctioned, then later started up like there was nothing wrong.

LTgun_94 · 04-14-2007, 12:25 AM

Yup i had a brand NEW msd opti due that to me, pnly it would run for a set amont of time every single time it ran. It would run for approximately 25 mins and then die, then when it cooled off it fired right back up! Something in mine was heat sensitive...not saying yours is but just throwing some things out there!

BJPZ28 · 04-14-2007, 08:29 AM

I hope it's not the opti! I don't wanna go through that again. No takers on the ICM? I seen the same symtoms in 2 Blazers resolved with the ICM, but they don't have this stupid opti set-up thrown in the mix.