'96 S-10 4.3L Hard start when hot

[Mavigraph]

I started haveing a problem with my S-10 hard starting when hot. I mean like it cranks great cold or if I haven't driven it for about 4 hours, but drive it for 10 miles and run into Wal-Mart and come back out 15 minutes later and I have to hold the key for 12 sec. or longer (When it's cold I just hold the key for 1 to 2 sec. like I've always done.) And then when it does crank, for about 5 sec. the engine run's ruff. Then it run's like normal.

I've got a scanner and have no codes. I look at my streaming data and nothing seem's amiss.......HELP!

 

[Ignatz]

I just went thru some temperature related running problems with my older 92 TB 4.3 van. It almost sounds as if its getting too much fuel after it warms up. Does it act like its flooded when its warmed up? Would it start easier after going to Wal-Mart if you floored it while cranking?

 

[alreadygone]

Hard start is usually taken to mean slooow, labored crank. Is this the case, or cranks normally,just longer before it fires off? If normal crank, just for a longer than normal time period, then rough idle, you can expect to install a new fuel injector "spider" under the intake manifold.

Bob

 

[MrCritical]

How old is the fuel filter? Is this the original fuel pump?

Are you filling up with Wally World gas while you're there?

 

[XS650]

Originally Posted By: alreadygone
Hard start is usually taken to mean slooow, labored crank. Is this the case, or cranks normally,just longer before it fires off? If normal crank, just for a longer than normal time period, then rough idle, you can expect to install a new fuel injector "spider" under the intake manifold.

Bob


If they are like the 95s he may have throttle body injector. Engine code Z = throttle body, W = Central Port Injection (spider)

If it's a W code with the spider, here's a helpful page.
http://www.blazerforum.com/m_7118/mpage_1/key_/tm.htm

 

[Mavigraph]

No, the cranking speed is normal. I do have the SCPI Engine Code=X. I've replace the fuel filter every 15,000. (But this last fuel filter is my first puralator brand.) I also will say this when the temp is mid 30's or lower the problem seem's to go away. This has been going on for three month's. When it first happened I ran a can of Seafoam with a full tank of gas back to back. It did seem to improve some what. Also I've cleaned my MAF and IAC. With no improvement. My personal feeling is it may be my spider but I want to make sure I've covered the simple stuff first and was hoping somebody has already experinced this problem first hand. Oh! and fuel pump was replace at 60,000 miles by dealer. I now have 215,000 or the od.

If spider was hoping you all could give me pointers on what parts I would need and what to expect.

 

[XS650]

Originally Posted By: Mavigraph


If spider was hoping you all could give me pointers on what parts I would need and what to expect.


That link I posted a couple of posts up is a good start. The article rambles a bit but it does mention a pressure regulator that can cause problems. The regulator is inexpensive (compared to the spider). IIRC, it says you can spot a leaky regulator by looking at it once you dig down to the level where you can see it. IIRC, the regulators are available at autoparts stores but not dealers.

If you decide to buy factory parts, gmpartsdirect.com beats local dealer prices by a bunch.

 

[wavinwayne]

I had a problem similar to this when I was driving my FIL's '94 Blazer a couple of summers ago. I used the brake booster vacuum hose to slowly suck up a can of Seafoam. Then, I let the Blazer sit for 10 minutes. After I started it, it blew a big cloud of white smoke and ran rough for a minute, then smoothed out to normal. The Blazer didn't give me any more problems for the 2 more months that I drove it.

I understand that the intake system on the 95 & newer Blazers is different (not sure how), so my fix might not do you any good.