2.9 loses power when warmed up


NMB2

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as the title says my 2.9 in my 88 B2 loses power significantly when warm, not nessesarily the water temp because it doesnt have a "set" spot where it loses but moreso the ambient temp outside, power loss isnt so much apparent at night when its cool, but definitly during the hot days.... doesnt become harder to start or spudder or anything like that... just feels like its very bogged down, sounds that way too, i have an intake and exhaust system so its easy to hear it too. On top of that my fuel mileage sucks, i feel the two problems probably have something to do with eachother. it has new ignition parts including tfi mod, the extreme that i fear it may be is a clogged cat(s). Any other ideas?
 


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Area 52

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Assuming your ignition system is in good shape, you have two symptoms that could point to the coolant temp sensor. This sensor is a variable resistor that has a calibrated resistance to match a given coolant temperature. The signal through the CTS feeds back to the computer; computer then adjusts injector pulse width (more fuel/less fuel) based on the conditions. Check the CTS with an ohmmeter; do a search for the test result chart that shows ohms by temp.
 

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similar issue

I have an 88 ranger 4x4. Just put a new tranny in it. Having some of the same issues. though i haven't noticed if the outside temp has much to do with it. But engine seems to run fine briefly after starting but after about 20 minutes, engine will spudder and loose power, you can floor and nothing will happen. Gas mileage is horrible, intermittent black exhaust with loss of power. Once in a while it will die on me or idle rough while stopped. I to thought the coolant temp and replaced that and nothing changed. I am going nuts trying to pinpoint this issue. Even brought it in, truck wouldn't act up for mechanic told me it was the best ranger he'd seen in years. Same crap on the freeway on the ride home. Does anyone have any clue of what direction I should go.:yahoo:
 

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I'd test the fuel pressure. You should be able to pick up a fuel pressure tester for about 60 bucks. I'd check your air filter too.
 

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have done both, still having problems
 

NMB2

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tested fuel pressure and was fine, also no dice on the CTS, instead of testing it i just replaced it. truck acts exactly the same. Im going to probably go ahead and replace the cat today and see what that does. Hopefully it fixes it.
 

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Have either of you 2 retreived codes from your respective vehicles?
 

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codes

tried pulling some codes but was kind-of unsure if I was doing it right. I was leaning towards the cat being clogged and then strangely enough exhaust blew on the way home, engine still stuttering and dogging. Could all issues be from clogged cat?
 
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IMenriched

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getting code could help point to a solution rather than just replacing parts.

that said it could still be more than 1 thing giving you fits...but codes should help clear things up as to what is going on.
 

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got a code reader, only code it pulls is 11, it doesnt have anything stored either. Yesterday i replaced both the cat and the 02 sensor... problem still not solved. checked fuel pressure, stays right at about 34psi on the rail.... I wish i could remember when it started acting this way because i did quite a few "mods" at once, Im starting to wonder if my intake is the problem? could the air charge being too hot be the problem?
 

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when i bought this thing last year in albuquerque it was the cool part of the year so this is actually the first summer having it and expieriencing this issue at such an extreme, shortly after buying it I did a few "upgrades" including intake stuff and exhaust.





that intake tube gets pretty hot, should I bother with a new one or insulating that one? perhaps cutting in the wheel well to get a colder air charge going into the filter, or is this irrelevent to my problem?
 

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Where's the air sensor? No wonder you're having problems. Put the stock air filter box and air sensor back on. It will provide more than enough cold intake air and the stock filter will keep fine dirt particles out. The cone filter you have passes fine dirt particles.
 

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Looks good..but...I'll agree that it is sucking heat in from the engine compartment.

couple this with warmer southern temps

Also, when was the last time the fuel filter was changed?? (considering that no codes were tripped)
 

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the air sensor is in the upper intake, not the airbox. also I routed the intake a little differently today so it pulls air straight through the grill, actually using the same hole as the stock intake. No difference. Problem still is there. As for the fuel filter... dont know when it was replaced but I dont think its a fuel delivery issue, pressure is fine....

i spoke with the previous owner today and he says that it did this before i owned it too, On hot days..... so scratch the air intake off the list i guess....

map senser, air charge temp sensor? Im stumped.
 

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yea my ranger does this too not always but every so often on realy hot days and i have my stock air filter and box i just replaced the fuel pumps and filter, map sensor, iac valve, about the only sensor i can think of thats left that i havent changed yet is the tp sensor but im not even sure if that would affect it or not, am i missing any sensors cuz i cant think of anymore rite now?
 


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