hesitation or miss?

[NWMO 95 Prizm Lsi]

Good evening all,

I just purchased a 95' prizm Lsi last week and drove it home some 400+ miles today. The car appears to be in great shape for 189,000 miles. The 1.8L motor runs smoothly and even through all acceleration or even under load (such as pulling a hill). Ran it up to 5,000 rpm getting on the highway and it feels great. There is however, a hesitation when I am trying to maintain a speed w/o much pull. Little grade or downhill, it will miss or hiccup when I try to maintain speed. If I accelerate or coast, it doesn't do it.

The shop I purchased the car from just serviced the cap,plugs & wires (not sure about coils). I assume he was trying to alleviate this hiccup w/o success. I will speak with him tomorrow and see what brand of parts were used and see what he has to say. I'm a tinkerer and from minimal past experience, I was leaning toward fuel delivery issue (filters, etc.). However, after reading some other posts, it may very well be part of the ignition system acting up. Any help is appreciated and TIA.

Chris

Update

I spoke with the seller this morning. New plugs were NGK, he thought wires were likely Borg Warner and the cap and rotor probably came from NAPA. He hadn't seen and I don't see any CEL or codes at this time. He thought if it occured at the same RPM each time it may point towards TPS, but I'm pretty sure it was behaving the same at 60 mph and 70 mph. The timing belt was serviced about 50,000 miles ago and the car received a replacement transmission recently. The old tranny apparently lost 3rd gear syncro, so a donor transmission from the junkyard (reported to have 85,000 miles on it) was installed.

Thanks again

[NWMO 95 Prizm Lsi]

More info,

I notice this the most when driving around town, if I accelerate normally, somewhere around 2300-2500 rpm it will buck to beat the band, not just miss a little. If I shift early in first and second and accelerate more aggresively in third, it will pull right through.

I'm green on these cars and just thinking out loud to generate some feedback and ideas. Seems to be more than a miss, like loss of fuel or temporarily out of time. I drove a work truck that behaved similarly at low rpm from time to time. Seems a litte worse when cold, better after going down the road some. Only last for a second, but will hiccup a few times if I stay on the gas.

Idles fine and accelarates (aggresively) well, so it would seem fuel delivery is ok.
New plugs and wires.
Timing advance? How monitored and controlled? (I will look on the net for a Haynes tonight)

Since I'm not sure where to start, I will start with the easy stuff.

Check plugs/wires/etc. What resistance should I be looking for on wires?
Look for evidence of arcing etc.

Timing advance?

Any help appreciated.

Chris

[NWMO 95 Prizm Lsi]

Good evening all,

At just over 800 miles since picking the car up a week ago, and knowing it wasn't quite right, I finally got a CEL. Code 41, TPS - trouble area, TPS or ECM circuit. Haynes pages 6-13 and 6-14 lay it out pretty well. I have a few feeler guages, but can't read the thickness anymore. I gues it is time to get some new ones. Is there anything to watch out for being a first timer?

Autozone wanted $100 for a new TPS, I will likely lean towards NAPA or CarQuest IF a new one is needed. Hopefully this one is ok and just needs adjustment. I happened to ask at Autozone today as I picked up my manual, most everyone else carried Chiltons, or didn't have 92036 on the shelf. Checked the web last night and everyone had pretty similar pricing, so fortunately I picked it up today. TIA for any tips and while I don't like the idea of a replacement, it is nice to find the problem and not have to keep guessing/searching.

Chris

[NWMO 95 Prizm Lsi]

Hey all,

After playing with it a bit, I felt like I got it adjusted so IDL-E2 was reading as it should at 0.016" and 0.035". All I get between VTA and E2 is infinity, regardless of what I do.

Any recommendations on best spot to get a new TPS? I will call around on Monday and price. I am also going to speak with the seller (who owns a shop) and see if he will work with me on it.

TIA

Chris

[trife96]

dude, my friends 94 corolla 1.6 was "hick-uping" like u say. We did a small tune up (which was way overdue!) But after pressure washing the engine bay, changed spark plugs, rotor, cap, fuel filter, and a can of Seafoam.

power was restored, and no more hick-ups...I think it was the seafoam, all though the plugs were done for

[NWMO 95 Prizm Lsi]

Hey all,

Purchased a new BWD throttle position sensor from O'Reillys ($90, lifetime warranty) and installed it this evening (went better than expected). Took about a 15 mile test drive and things are much better . I'm still getting use to the car, but it sure is nice to drive w/o that little hesitation popping up frequently. Replaced the washer pump last night as well so for now I'm just driving it and waiting for the next little thing that needs attention.

I did notice my air filter housing is lacking 2 of the "hold down" clips, doesn't look like it is hurting anything, but thought I would mention it.

If all goes well, I will put 8k-10k miles on it before replacing the left side half axle (unless it starts making noise and needs addressed sooner) and putting some new tires on it. Currently running 1 Bridgestone, 1 Firestone, 1 Douglas and 1 BF Goodrich, all xxx/185 R14, non with a lot of tread though the fronts probably have 3/32" or so.

Chris