Hello all,

My car is an '89 740 turbo. This is the problem. Sometimes, not always, when starting from a dead-stop I get a slight hesitation when giving it throttle after which it almost instantly catches. It feels like a hesitation caused by some kind of delayed fuel response. However that's not all it does. When driving at speeds where you get up and down variation, like around town driving, start-stop stuff, it occasionally bogs down, again like it's not getting fuel. If you hold your foot on the gas pedal at the same position without variation, then you can see the tach dipping down during the bogging phase then it will regain rpms and drive as normal. This will almost never happen at highway speeds where there is a more or less constant speed and rpms for an extended period of time. However if I slow down momentarily and get back on the gas it may stumble again. The other thing is you can get it to recover quicker if you take your foot off the gas and give it gas again, which usually causes the rpms to surge higher momentarily until you let off the gas to get rpms and acceleration back into the normal range. Now this is the interesting bit - all the parts and work that has been done recently: TB cleaned along with IAC yesterday, one vacuum hose replaced (obviously wrong size and may have been causing a leak), FPR, ignition module (fixed the jumping tach-stalling problem from earlier posts), new coil, knock sensor (overtightened perhaps?), radio suppression relay, both fuel pumps, fuel filter, new distributor/hall sensor, new cap, rotor, wires, plugs (look okay), used Mitsu turbo with no obvious signs of excess wear, and finally no excessive amount of oil in intercooler or hoses beyond what would be considered normal for a turbo. Finally I noticed doing the TB cleaning that a couple of the intercooler hoses (coming out of TB and coming out of intercooler, and between turbo and intercooler [little connector hose])look pretty well ratty inside and will need replacing but don't appear to have any wear that would be creating holes. Anyway, if the hoses had holes wouldn't they affect the car the whole time it was running instead of intermittently? Well, sorry this is so long but I've done so much on this car it's tough to figure out what could be causing this most recent problem. Only thing I can think is it seems to be throttle related.

Matt Campbell
'89 740 Turbo wagon