akthunder

Alright, so let me start off my saying I've got an 87 motor home built on a one ton pickup frame with an automatic transmission and the 22re engine. So I've been having some fuel issues with this truck and I've since replaced the fuel filter, fuel pump, pressure regulator, and a regular tune up. So it's been pretty hard to start when cold, easy when it's warmed up. When I start it cold I have to turn the key on about 4 seconds, turn it off and turn it back on about 5 times and usually fires up. When I press on the gas it revs up just fine but when I put it into gear and try to drive off before letting the engine run for about 1 minute the engine bogs down, pops, and has no power. But after about a minute or so (when it starts to warm up a little) it runs just fine. Now when I get to around running temp there is a slight surge to the idle, but runs good enough. When starting the car warm it usually has a more drastic idle for a few dips then it levels off to the "normal" surge.

So today, after my truck sitting for only 1 full day, it was terribly hard to start. When I did get it running the idle was very low, backfiring, and kept idling out (rpm just drops so low it just can't run and the engine stops). After a while I got it to run for about 25-30 seconds before the problems again. Now, when firing it up if I am on the gas right away the engine will rev up, start popping, and the idle crashes. If I press on the gas after it's been running for a little bit it just kills it right then and there.

Any suggestions for what it could be? Need any more info? Sorry if it's a little scattered in places, I'm just trying to be as thorough as possible.

thook

Sounds very sensor related to me. I'd start by checking/testing the coolant temp sensor.

There's two on the front of the engine; one's the cold start switch...brown, the other is the coolant temp sensor....green. Pull the green one out and cork the hole. Put the sensor in a pot of water and hook it up to an ohm meter. On the meter, use the setting just high enough to accurately read the resistance.......like the 10k ohms, or 20k if you don't have 10k on the unit. Anyway, the resistance should be higher with room temp water......like 1500 to 3k ohms. Really not important, yet. What's important is how the resistance changes.

With the meter still hooked up, begin heating the water. Resistance should steadily drop. If not, you got a problem and need to replace it. O'Reilly's has some new BW units that work pretty as far as I've seen. If you can spring for Denso prices, do it. Or, try the folks at Nix99 on the web. Josh....Deathcougar on YT...works there. He'll set you up if they have any on hand.

*Record your ohm readings according to temp (you'll need a thermometer) for your reference and compare to this chart: http://personal.utulsa.edu/~nathan-b...40engineco.pdf

BTW, I'd suggest running the test on the vehicle by back probing the sensor and monitoring voltage, but since it's running like dog doo it wouldn't be so easy.

As well......if the sensor looks good, move to testing the intake air temp sensor on the airflow meter and/or the idle air control valve.

akthunder

Alright, I thought I would just chime in here for an update. After tinkering around with a few things I couldn't get the problem figured out. So I removed the -RE intake and installed the -R intake. So it's now carbureted and I still had the same problem. Turns out it was something with the coil. Whether it was the coil going bad or the signal to the coil from the computer going bad I'm not too sure. But after changing it to the older coil it ran much better. I still have some minor adjustments to take care of but the engine does in fact run now.