Hesitation w/o SES codes. Temp sensors?

Top Post!!!!!!!! Just woundering...You said you think it sat for a while? And all your fluids look lile crap....Ok did you replace the fuel when you Reinstalled the tank?How about looking at the fuel filter ? Get a fuel pressure reading......Before you start slapping sensors in it...Could be just a guess of course Weak fuel pump,Clogged fuel filter,leaking fuelpressure regulator,Didnt 91s have distributor caps?Obviously they ha a fuel problem before you got it So lets start here..IEven though you passed an emissions inspection we would still like to know what pressure you are running.. Steve C Hesitation w/o SES codes. Temp sensors? Group: alt.autos.4x4.chevy-trucks Date: Sun, Aug 15, 2004, 9:25am (CDT-2) From: snipped-for-privacy@comcast.net (Elliott) Bought this used a few months ago - I think is sat a few years before that.

1991 S-10 4.3L TBI has new O2, TPI sensors. Had a "tune-up": plugs, wires, EGR cleaned Vac is good (dealer checked) Timing light looks good (about 10BTDC and advances fine). Gas tank was improperly installed (fixed) - seems likely new fule pump. passed inspection, has no codes set, but runs like crap. It isn't missing, but... It hesitates badly, lacks power and chuggles a little when cruising. Known problem: Temp sensors (could that do it?) Also: I belive it sat for a long long time before I bought it. The water was very rusty and had to be flushed >10x to get it to stay green (still rusty too). This is why I haven't yet replaced the temp sensors. The cat-conv. is also very old (but doesn't backfire, etc).

Thanks for a reply... progress but not done... Answ. to your questions: I didn't replace the fuel or filter. I didn't 'reinstall' the tank but simply tightened the hose-clamps on the filler-spout and vent hose (so it didn't leak when filled), and tightened up the rear strap that was looose. I 'slapped' in TPS & 02 sensors because they were amazingly cheep ( Top Post!!!!!!!!

I'm going to top post this as there is too much to read through. I have similar problems (my thread is 'the vacuum monster'). Like you I disconnected the EGR vale and had some improvement.

Today I gave up and stopped by an old mechanic's place I know of. As luck would have he wasn't all that busy and anyway it would only take 15 minutes to fix. No parts to buy. Told me to come back after lunch. I did and twenty minutes later I had gained 100 horsepower.

The poor old trucks butt was plugged up. Air and fuel in but not much coming out, - sorta like you eating lunch and then not being able to getrid of it. The Cat was plugged. He said they can do a pressure test on the tail pipe but didn't bother as he could tell from the sound of the engine revving up.

Dave